2023-06-15 07:53:29

by Anup Patel

Subject: [PATCH v3 00/10] RISC-V KVM in-kernel AIA irqchip

This series adds in-kernel AIA irqchip to KVM RISC-V which trap-n-emulate
IMSIC and APLIC MSI-mode for Guest. The APLIC MSI-mode trap-n-emulate is
optional so KVM user space can emulate APLIC entirely in user space.

The use of IMSIC HW guest files to accelerate IMSIC virtualization will be
done as separate series since this depends on AIA irqchip drivers to be
upstreamed. This series has no dependency on the AIA irqchip drivers.

There is also a KVM AIA irq-bypass (or device MSI virtualization) series
under development which depends on this series and upcoming IOMMU driver
series.

These patches (or this series) can also be found in the
riscv_kvm_aia_irqchip_v3 branch at: https://github.com/avpatel/linux.git

Changes since v2:
- Added KVM_CAP_IRQCHIP in PATCH5
- Fix check for KVM_DEV_RISCV_AIA_CONFIG_IDS write in PATCH6
- Fix APLIC_IRQ_STATE_ENPEND usage in PATCH7

Changes since v1:
- Rebased on Linux-6.4-rc6
- Addressed Atish's comment in PATCH6
- Added comments in arch/riscv/include/uapi/asm/kvm.h about APLIC and
IMSIC device attribute type

Anup Patel (10):
RISC-V: KVM: Implement guest external interrupt line management
RISC-V: KVM: Add IMSIC related defines
RISC-V: KVM: Add APLIC related defines
RISC-V: KVM: Set kvm_riscv_aia_nr_hgei to zero
RISC-V: KVM: Skeletal in-kernel AIA irqchip support
RISC-V: KVM: Implement device interface for AIA irqchip
RISC-V: KVM: Add in-kernel emulation of AIA APLIC
RISC-V: KVM: Expose APLIC registers as attributes of AIA irqchip
RISC-V: KVM: Add in-kernel virtualization of AIA IMSIC
RISC-V: KVM: Expose IMSIC registers as attributes of AIA irqchip

arch/riscv/include/asm/kvm_aia.h | 107 ++-
arch/riscv/include/asm/kvm_aia_aplic.h | 58 ++
arch/riscv/include/asm/kvm_aia_imsic.h | 38 +
arch/riscv/include/asm/kvm_host.h | 4 +
arch/riscv/include/uapi/asm/kvm.h | 72 ++
arch/riscv/kvm/Kconfig | 4 +
arch/riscv/kvm/Makefile | 3 +
arch/riscv/kvm/aia.c | 274 +++++-
arch/riscv/kvm/aia_aplic.c | 619 ++++++++++++++
arch/riscv/kvm/aia_device.c | 673 +++++++++++++++
arch/riscv/kvm/aia_imsic.c | 1083 ++++++++++++++++++++++++
arch/riscv/kvm/main.c | 3 +-
arch/riscv/kvm/vcpu.c | 2 +
arch/riscv/kvm/vm.c | 118 +++
include/uapi/linux/kvm.h | 2 +
15 files changed, 3027 insertions(+), 33 deletions(-)
create mode 100644 arch/riscv/include/asm/kvm_aia_aplic.h
create mode 100644 arch/riscv/include/asm/kvm_aia_imsic.h
create mode 100644 arch/riscv/kvm/aia_aplic.c
create mode 100644 arch/riscv/kvm/aia_device.c
create mode 100644 arch/riscv/kvm/aia_imsic.c

--
2.34.1

2023-06-15 07:54:46

by Anup Patel

Subject: [PATCH v3 02/10] RISC-V: KVM: Add IMSIC related defines

We add IMSIC related defines in a separate header so that different
parts of KVM code can share it. Once AIA drivers are merged will
have a common IMSIC header shared by both KVM and IRQCHIP driver.

Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Atish Patra <[email protected]>
---
arch/riscv/include/asm/kvm_aia_imsic.h | 38 ++++++++++++++++++++++++++
arch/riscv/kvm/aia.c | 3 +-
2 files changed, 39 insertions(+), 2 deletions(-)
create mode 100644 arch/riscv/include/asm/kvm_aia_imsic.h

diff --git a/arch/riscv/include/asm/kvm_aia_imsic.h b/arch/riscv/include/asm/kvm_aia_imsic.h
new file mode 100644
index 000000000000..da5881d2bde0
--- /dev/null
+++ b/arch/riscv/include/asm/kvm_aia_imsic.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ * Copyright (C) 2022 Ventana Micro Systems Inc.
+ */
+#ifndef __KVM_RISCV_AIA_IMSIC_H
+#define __KVM_RISCV_AIA_IMSIC_H
+
+#include <linux/types.h>
+#include <asm/csr.h>
+
+#define IMSIC_MMIO_PAGE_SHIFT 12
+#define IMSIC_MMIO_PAGE_SZ (1UL << IMSIC_MMIO_PAGE_SHIFT)
+#define IMSIC_MMIO_PAGE_LE 0x00
+#define IMSIC_MMIO_PAGE_BE 0x04
+
+#define IMSIC_MIN_ID 63
+#define IMSIC_MAX_ID 2048
+
+#define IMSIC_EIDELIVERY 0x70
+
+#define IMSIC_EITHRESHOLD 0x72
+
+#define IMSIC_EIP0 0x80
+#define IMSIC_EIP63 0xbf
+#define IMSIC_EIPx_BITS 32
+
+#define IMSIC_EIE0 0xc0
+#define IMSIC_EIE63 0xff
+#define IMSIC_EIEx_BITS 32
+
+#define IMSIC_FIRST IMSIC_EIDELIVERY
+#define IMSIC_LAST IMSIC_EIE63
+
+#define IMSIC_MMIO_SETIPNUM_LE 0x00
+#define IMSIC_MMIO_SETIPNUM_BE 0x04
+
+#endif
diff --git a/arch/riscv/kvm/aia.c b/arch/riscv/kvm/aia.c
index 1cee75a8c883..c78c06d99e39 100644
--- a/arch/riscv/kvm/aia.c
+++ b/arch/riscv/kvm/aia.c
@@ -15,6 +15,7 @@
#include <linux/percpu.h>
#include <linux/spinlock.h>
#include <asm/hwcap.h>
+#include <asm/kvm_aia_imsic.h>

struct aia_hgei_control {
raw_spinlock_t lock;
@@ -364,8 +365,6 @@ static int aia_rmw_iprio(struct kvm_vcpu *vcpu, unsigned int isel,
return KVM_INSN_CONTINUE_NEXT_SEPC;
}

-#define IMSIC_FIRST 0x70
-#define IMSIC_LAST 0xff
int kvm_riscv_vcpu_aia_rmw_ireg(struct kvm_vcpu *vcpu, unsigned int csr_num,
unsigned long *val, unsigned long new_val,
unsigned long wr_mask)
--
2.34.1

2023-06-15 07:59:36

by Anup Patel

Subject: [PATCH v3 06/10] RISC-V: KVM: Implement device interface for AIA irqchip

We implement KVM device interface for in-kernel AIA irqchip so that
user-space can use KVM device ioctls to create, configure, and destroy
in-kernel AIA irqchip.

Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Atish Patra <[email protected]>
---
arch/riscv/include/asm/kvm_aia.h | 132 +++++--
arch/riscv/include/uapi/asm/kvm.h | 45 +++
arch/riscv/kvm/Makefile | 1 +
arch/riscv/kvm/aia.c | 11 +
arch/riscv/kvm/aia_device.c | 623 ++++++++++++++++++++++++++++++
include/uapi/linux/kvm.h | 2 +
6 files changed, 772 insertions(+), 42 deletions(-)
create mode 100644 arch/riscv/kvm/aia_device.c

diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
index 3bc0a0e47a15..a1281ebc9b92 100644
--- a/arch/riscv/include/asm/kvm_aia.h
+++ b/arch/riscv/include/asm/kvm_aia.h
@@ -20,6 +20,33 @@ struct kvm_aia {

/* In-kernel irqchip initialized */
bool initialized;
+
+ /* Virtualization mode (Emulation, HW Accelerated, or Auto) */
+ u32 mode;
+
+ /* Number of MSIs */
+ u32 nr_ids;
+
+ /* Number of wired IRQs */
+ u32 nr_sources;
+
+ /* Number of group bits in IMSIC address */
+ u32 nr_group_bits;
+
+ /* Position of group bits in IMSIC address */
+ u32 nr_group_shift;
+
+ /* Number of hart bits in IMSIC address */
+ u32 nr_hart_bits;
+
+ /* Number of guest bits in IMSIC address */
+ u32 nr_guest_bits;
+
+ /* Guest physical address of APLIC */
+ gpa_t aplic_addr;
+
+ /* Internal state of APLIC */
+ void *aplic_state;
};

struct kvm_vcpu_aia_csr {
@@ -38,8 +65,19 @@ struct kvm_vcpu_aia {

/* CPU AIA CSR context upon Guest VCPU reset */
struct kvm_vcpu_aia_csr guest_reset_csr;
+
+ /* Guest physical address of IMSIC for this VCPU */
+ gpa_t imsic_addr;
+
+ /* HART index of IMSIC extacted from guest physical address */
+ u32 hart_index;
+
+ /* Internal state of IMSIC for this VCPU */
+ void *imsic_state;
};

+#define KVM_RISCV_AIA_UNDEF_ADDR (-1)
+
#define kvm_riscv_aia_initialized(k) ((k)->arch.aia.initialized)

#define irqchip_in_kernel(k) ((k)->arch.aia.in_kernel)
@@ -50,10 +88,17 @@ DECLARE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
#define kvm_riscv_aia_available() \
static_branch_unlikely(&kvm_riscv_aia_available)

+extern struct kvm_device_ops kvm_riscv_aia_device_ops;
+
static inline void kvm_riscv_vcpu_aia_imsic_release(struct kvm_vcpu *vcpu)
{
}

+static inline int kvm_riscv_vcpu_aia_imsic_update(struct kvm_vcpu *vcpu)
+{
+ return 1;
+}
+
#define KVM_RISCV_AIA_IMSIC_TOPEI (ISELECT_MASK + 1)
static inline int kvm_riscv_vcpu_aia_imsic_rmw(struct kvm_vcpu *vcpu,
unsigned long isel,
@@ -64,6 +109,41 @@ static inline int kvm_riscv_vcpu_aia_imsic_rmw(struct kvm_vcpu *vcpu,
return 0;
}

+static inline void kvm_riscv_vcpu_aia_imsic_reset(struct kvm_vcpu *vcpu)
+{
+}
+
+static inline int kvm_riscv_vcpu_aia_imsic_inject(struct kvm_vcpu *vcpu,
+ u32 guest_index, u32 offset,
+ u32 iid)
+{
+ return 0;
+}
+
+static inline int kvm_riscv_vcpu_aia_imsic_init(struct kvm_vcpu *vcpu)
+{
+ return 0;
+}
+
+static inline void kvm_riscv_vcpu_aia_imsic_cleanup(struct kvm_vcpu *vcpu)
+{
+}
+
+static inline int kvm_riscv_aia_aplic_inject(struct kvm *kvm,
+ u32 source, bool level)
+{
+ return 0;
+}
+
+static inline int kvm_riscv_aia_aplic_init(struct kvm *kvm)
+{
+ return 0;
+}
+
+static inline void kvm_riscv_aia_aplic_cleanup(struct kvm *kvm)
+{
+}
+
#ifdef CONFIG_32BIT
void kvm_riscv_vcpu_aia_flush_interrupts(struct kvm_vcpu *vcpu);
void kvm_riscv_vcpu_aia_sync_interrupts(struct kvm_vcpu *vcpu);
@@ -99,50 +179,18 @@ int kvm_riscv_vcpu_aia_rmw_ireg(struct kvm_vcpu *vcpu, unsigned int csr_num,
{ .base = CSR_SIREG, .count = 1, .func = kvm_riscv_vcpu_aia_rmw_ireg }, \
{ .base = CSR_STOPEI, .count = 1, .func = kvm_riscv_vcpu_aia_rmw_topei },

-static inline int kvm_riscv_vcpu_aia_update(struct kvm_vcpu *vcpu)
-{
- return 1;
-}
-
-static inline void kvm_riscv_vcpu_aia_reset(struct kvm_vcpu *vcpu)
-{
-}
-
-static inline int kvm_riscv_vcpu_aia_init(struct kvm_vcpu *vcpu)
-{
- return 0;
-}
-
-static inline void kvm_riscv_vcpu_aia_deinit(struct kvm_vcpu *vcpu)
-{
-}
-
-static inline int kvm_riscv_aia_inject_msi_by_id(struct kvm *kvm,
- u32 hart_index,
- u32 guest_index, u32 iid)
-{
- return 0;
-}
-
-static inline int kvm_riscv_aia_inject_msi(struct kvm *kvm,
- struct kvm_msi *msi)
-{
- return 0;
-}
+int kvm_riscv_vcpu_aia_update(struct kvm_vcpu *vcpu);
+void kvm_riscv_vcpu_aia_reset(struct kvm_vcpu *vcpu);
+int kvm_riscv_vcpu_aia_init(struct kvm_vcpu *vcpu);
+void kvm_riscv_vcpu_aia_deinit(struct kvm_vcpu *vcpu);

-static inline int kvm_riscv_aia_inject_irq(struct kvm *kvm,
- unsigned int irq, bool level)
-{
- return 0;
-}
+int kvm_riscv_aia_inject_msi_by_id(struct kvm *kvm, u32 hart_index,
+ u32 guest_index, u32 iid);
+int kvm_riscv_aia_inject_msi(struct kvm *kvm, struct kvm_msi *msi);
+int kvm_riscv_aia_inject_irq(struct kvm *kvm, unsigned int irq, bool level);

-static inline void kvm_riscv_aia_init_vm(struct kvm *kvm)
-{
-}
-
-static inline void kvm_riscv_aia_destroy_vm(struct kvm *kvm)
-{
-}
+void kvm_riscv_aia_init_vm(struct kvm *kvm);
+void kvm_riscv_aia_destroy_vm(struct kvm *kvm);

int kvm_riscv_aia_alloc_hgei(int cpu, struct kvm_vcpu *owner,
void __iomem **hgei_va, phys_addr_t *hgei_pa);
diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
index 332d4a274891..047c8fc5bd71 100644
--- a/arch/riscv/include/uapi/asm/kvm.h
+++ b/arch/riscv/include/uapi/asm/kvm.h
@@ -204,6 +204,51 @@ enum KVM_RISCV_SBI_EXT_ID {
#define KVM_REG_RISCV_SBI_MULTI_REG_LAST \
KVM_REG_RISCV_SBI_MULTI_REG(KVM_RISCV_SBI_EXT_MAX - 1)

+/* Device Control API: RISC-V AIA */
+#define KVM_DEV_RISCV_APLIC_ALIGN 0x1000
+#define KVM_DEV_RISCV_APLIC_SIZE 0x4000
+#define KVM_DEV_RISCV_APLIC_MAX_HARTS 0x4000
+#define KVM_DEV_RISCV_IMSIC_ALIGN 0x1000
+#define KVM_DEV_RISCV_IMSIC_SIZE 0x1000
+
+#define KVM_DEV_RISCV_AIA_GRP_CONFIG 0
+#define KVM_DEV_RISCV_AIA_CONFIG_MODE 0
+#define KVM_DEV_RISCV_AIA_CONFIG_IDS 1
+#define KVM_DEV_RISCV_AIA_CONFIG_SRCS 2
+#define KVM_DEV_RISCV_AIA_CONFIG_GROUP_BITS 3
+#define KVM_DEV_RISCV_AIA_CONFIG_GROUP_SHIFT 4
+#define KVM_DEV_RISCV_AIA_CONFIG_HART_BITS 5
+#define KVM_DEV_RISCV_AIA_CONFIG_GUEST_BITS 6
+
+/*
+ * Modes of RISC-V AIA device:
+ * 1) EMUL (aka Emulation): Trap-n-emulate IMSIC
+ * 2) HWACCEL (aka HW Acceleration): Virtualize IMSIC using IMSIC guest files
+ * 3) AUTO (aka Automatic): Virtualize IMSIC using IMSIC guest files whenever
+ * available otherwise fallback to trap-n-emulation
+ */
+#define KVM_DEV_RISCV_AIA_MODE_EMUL 0
+#define KVM_DEV_RISCV_AIA_MODE_HWACCEL 1
+#define KVM_DEV_RISCV_AIA_MODE_AUTO 2
+
+#define KVM_DEV_RISCV_AIA_IDS_MIN 63
+#define KVM_DEV_RISCV_AIA_IDS_MAX 2048
+#define KVM_DEV_RISCV_AIA_SRCS_MAX 1024
+#define KVM_DEV_RISCV_AIA_GROUP_BITS_MAX 8
+#define KVM_DEV_RISCV_AIA_GROUP_SHIFT_MIN 24
+#define KVM_DEV_RISCV_AIA_GROUP_SHIFT_MAX 56
+#define KVM_DEV_RISCV_AIA_HART_BITS_MAX 16
+#define KVM_DEV_RISCV_AIA_GUEST_BITS_MAX 8
+
+#define KVM_DEV_RISCV_AIA_GRP_ADDR 1
+#define KVM_DEV_RISCV_AIA_ADDR_APLIC 0
+#define KVM_DEV_RISCV_AIA_ADDR_IMSIC(__vcpu) (1 + (__vcpu))
+#define KVM_DEV_RISCV_AIA_ADDR_MAX \
+ (1 + KVM_DEV_RISCV_APLIC_MAX_HARTS)
+
+#define KVM_DEV_RISCV_AIA_GRP_CTRL 2
+#define KVM_DEV_RISCV_AIA_CTRL_INIT 0
+
/* One single KVM irqchip, ie. the AIA */
#define KVM_NR_IRQCHIPS 1

diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile
index 8031b8912a0d..dd69ebe098bd 100644
--- a/arch/riscv/kvm/Makefile
+++ b/arch/riscv/kvm/Makefile
@@ -27,3 +27,4 @@ kvm-y += vcpu_sbi_hsm.o
kvm-y += vcpu_timer.o
kvm-$(CONFIG_RISCV_PMU_SBI) += vcpu_pmu.o vcpu_sbi_pmu.o
kvm-y += aia.o
+kvm-y += aia_device.o
diff --git a/arch/riscv/kvm/aia.c b/arch/riscv/kvm/aia.c
index 18c442c15ff2..585a3b42c52c 100644
--- a/arch/riscv/kvm/aia.c
+++ b/arch/riscv/kvm/aia.c
@@ -631,6 +631,14 @@ int kvm_riscv_aia_init(void)
if (rc)
return rc;

+ /* Register device operations */
+ rc = kvm_register_device_ops(&kvm_riscv_aia_device_ops,
+ KVM_DEV_TYPE_RISCV_AIA);
+ if (rc) {
+ aia_hgei_exit();
+ return rc;
+ }
+
/* Enable KVM AIA support */
static_branch_enable(&kvm_riscv_aia_available);

@@ -642,6 +650,9 @@ void kvm_riscv_aia_exit(void)
if (!kvm_riscv_aia_available())
return;

+ /* Unregister device operations */
+ kvm_unregister_device_ops(KVM_DEV_TYPE_RISCV_AIA);
+
/* Cleanup the HGEI state */
aia_hgei_exit();
}
diff --git a/arch/riscv/kvm/aia_device.c b/arch/riscv/kvm/aia_device.c
new file mode 100644
index 000000000000..7ab555121872
--- /dev/null
+++ b/arch/riscv/kvm/aia_device.c
@@ -0,0 +1,623 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ * Copyright (C) 2022 Ventana Micro Systems Inc.
+ *
+ * Authors:
+ * Anup Patel <[email protected]>
+ */
+
+#include <linux/bits.h>
+#include <linux/kvm_host.h>
+#include <linux/uaccess.h>
+#include <asm/kvm_aia_imsic.h>
+
+static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx)
+{
+ struct kvm_vcpu *tmp_vcpu;
+
+ for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
+ tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
+ mutex_unlock(&tmp_vcpu->mutex);
+ }
+}
+
+static void unlock_all_vcpus(struct kvm *kvm)
+{
+ unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1);
+}
+
+static bool lock_all_vcpus(struct kvm *kvm)
+{
+ struct kvm_vcpu *tmp_vcpu;
+ unsigned long c;
+
+ kvm_for_each_vcpu(c, tmp_vcpu, kvm) {
+ if (!mutex_trylock(&tmp_vcpu->mutex)) {
+ unlock_vcpus(kvm, c - 1);
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static int aia_create(struct kvm_device *dev, u32 type)
+{
+ int ret;
+ unsigned long i;
+ struct kvm *kvm = dev->kvm;
+ struct kvm_vcpu *vcpu;
+
+ if (irqchip_in_kernel(kvm))
+ return -EEXIST;
+
+ ret = -EBUSY;
+ if (!lock_all_vcpus(kvm))
+ return ret;
+
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ if (vcpu->arch.ran_atleast_once)
+ goto out_unlock;
+ }
+ ret = 0;
+
+ kvm->arch.aia.in_kernel = true;
+
+out_unlock:
+ unlock_all_vcpus(kvm);
+ return ret;
+}
+
+static void aia_destroy(struct kvm_device *dev)
+{
+ kfree(dev);
+}
+
+static int aia_config(struct kvm *kvm, unsigned long type,
+ u32 *nr, bool write)
+{
+ struct kvm_aia *aia = &kvm->arch.aia;
+
+ /* Writes can only be done before irqchip is initialized */
+ if (write && kvm_riscv_aia_initialized(kvm))
+ return -EBUSY;
+
+ switch (type) {
+ case KVM_DEV_RISCV_AIA_CONFIG_MODE:
+ if (write) {
+ switch (*nr) {
+ case KVM_DEV_RISCV_AIA_MODE_EMUL:
+ break;
+ case KVM_DEV_RISCV_AIA_MODE_HWACCEL:
+ case KVM_DEV_RISCV_AIA_MODE_AUTO:
+ /*
+ * HW Acceleration and Auto modes only
+ * supported on host with non-zero guest
+ * external interrupts (i.e. non-zero
+ * VS-level IMSIC pages).
+ */
+ if (!kvm_riscv_aia_nr_hgei)
+ return -EINVAL;
+ break;
+ default:
+ return -EINVAL;
+ };
+ aia->mode = *nr;
+ } else
+ *nr = aia->mode;
+ break;
+ case KVM_DEV_RISCV_AIA_CONFIG_IDS:
+ if (write) {
+ if ((*nr < KVM_DEV_RISCV_AIA_IDS_MIN) ||
+ (*nr >= KVM_DEV_RISCV_AIA_IDS_MAX) ||
+ ((*nr & KVM_DEV_RISCV_AIA_IDS_MIN) !=
+ KVM_DEV_RISCV_AIA_IDS_MIN) ||
+ (kvm_riscv_aia_max_ids <= *nr))
+ return -EINVAL;
+ aia->nr_ids = *nr;
+ } else
+ *nr = aia->nr_ids;
+ break;
+ case KVM_DEV_RISCV_AIA_CONFIG_SRCS:
+ if (write) {
+ if ((*nr >= KVM_DEV_RISCV_AIA_SRCS_MAX) ||
+ (*nr >= kvm_riscv_aia_max_ids))
+ return -EINVAL;
+ aia->nr_sources = *nr;
+ } else
+ *nr = aia->nr_sources;
+ break;
+ case KVM_DEV_RISCV_AIA_CONFIG_GROUP_BITS:
+ if (write) {
+ if (*nr >= KVM_DEV_RISCV_AIA_GROUP_BITS_MAX)
+ return -EINVAL;
+ aia->nr_group_bits = *nr;
+ } else
+ *nr = aia->nr_group_bits;
+ break;
+ case KVM_DEV_RISCV_AIA_CONFIG_GROUP_SHIFT:
+ if (write) {
+ if ((*nr < KVM_DEV_RISCV_AIA_GROUP_SHIFT_MIN) ||
+ (*nr >= KVM_DEV_RISCV_AIA_GROUP_SHIFT_MAX))
+ return -EINVAL;
+ aia->nr_group_shift = *nr;
+ } else
+ *nr = aia->nr_group_shift;
+ break;
+ case KVM_DEV_RISCV_AIA_CONFIG_HART_BITS:
+ if (write) {
+ if (*nr >= KVM_DEV_RISCV_AIA_HART_BITS_MAX)
+ return -EINVAL;
+ aia->nr_hart_bits = *nr;
+ } else
+ *nr = aia->nr_hart_bits;
+ break;
+ case KVM_DEV_RISCV_AIA_CONFIG_GUEST_BITS:
+ if (write) {
+ if (*nr >= KVM_DEV_RISCV_AIA_GUEST_BITS_MAX)
+ return -EINVAL;
+ aia->nr_guest_bits = *nr;
+ } else
+ *nr = aia->nr_guest_bits;
+ break;
+ default:
+ return -ENXIO;
+ };
+
+ return 0;
+}
+
+static int aia_aplic_addr(struct kvm *kvm, u64 *addr, bool write)
+{
+ struct kvm_aia *aia = &kvm->arch.aia;
+
+ if (write) {
+ /* Writes can only be done before irqchip is initialized */
+ if (kvm_riscv_aia_initialized(kvm))
+ return -EBUSY;
+
+ if (*addr & (KVM_DEV_RISCV_APLIC_ALIGN - 1))
+ return -EINVAL;
+
+ aia->aplic_addr = *addr;
+ } else
+ *addr = aia->aplic_addr;
+
+ return 0;
+}
+
+static int aia_imsic_addr(struct kvm *kvm, u64 *addr,
+ unsigned long vcpu_idx, bool write)
+{
+ struct kvm_vcpu *vcpu;
+ struct kvm_vcpu_aia *vcpu_aia;
+
+ vcpu = kvm_get_vcpu(kvm, vcpu_idx);
+ if (!vcpu)
+ return -EINVAL;
+ vcpu_aia = &vcpu->arch.aia_context;
+
+ if (write) {
+ /* Writes can only be done before irqchip is initialized */
+ if (kvm_riscv_aia_initialized(kvm))
+ return -EBUSY;
+
+ if (*addr & (KVM_DEV_RISCV_IMSIC_ALIGN - 1))
+ return -EINVAL;
+ }
+
+ mutex_lock(&vcpu->mutex);
+ if (write)
+ vcpu_aia->imsic_addr = *addr;
+ else
+ *addr = vcpu_aia->imsic_addr;
+ mutex_unlock(&vcpu->mutex);
+
+ return 0;
+}
+
+static gpa_t aia_imsic_ppn(struct kvm_aia *aia, gpa_t addr)
+{
+ u32 h, l;
+ gpa_t mask = 0;
+
+ h = aia->nr_hart_bits + aia->nr_guest_bits +
+ IMSIC_MMIO_PAGE_SHIFT - 1;
+ mask = GENMASK_ULL(h, 0);
+
+ if (aia->nr_group_bits) {
+ h = aia->nr_group_bits + aia->nr_group_shift - 1;
+ l = aia->nr_group_shift;
+ mask |= GENMASK_ULL(h, l);
+ }
+
+ return (addr & ~mask) >> IMSIC_MMIO_PAGE_SHIFT;
+}
+
+static u32 aia_imsic_hart_index(struct kvm_aia *aia, gpa_t addr)
+{
+ u32 hart, group = 0;
+
+ hart = (addr >> (aia->nr_guest_bits + IMSIC_MMIO_PAGE_SHIFT)) &
+ GENMASK_ULL(aia->nr_hart_bits - 1, 0);
+ if (aia->nr_group_bits)
+ group = (addr >> aia->nr_group_shift) &
+ GENMASK_ULL(aia->nr_group_bits - 1, 0);
+
+ return (group << aia->nr_hart_bits) | hart;
+}
+
+static int aia_init(struct kvm *kvm)
+{
+ int ret, i;
+ unsigned long idx;
+ struct kvm_vcpu *vcpu;
+ struct kvm_vcpu_aia *vaia;
+ struct kvm_aia *aia = &kvm->arch.aia;
+ gpa_t base_ppn = KVM_RISCV_AIA_UNDEF_ADDR;
+
+ /* Irqchip can be initialized only once */
+ if (kvm_riscv_aia_initialized(kvm))
+ return -EBUSY;
+
+ /* We might be in the middle of creating a VCPU? */
+ if (kvm->created_vcpus != atomic_read(&kvm->online_vcpus))
+ return -EBUSY;
+
+ /* Number of sources should be less than or equals number of IDs */
+ if (aia->nr_ids < aia->nr_sources)
+ return -EINVAL;
+
+ /* APLIC base is required for non-zero number of sources */
+ if (aia->nr_sources && aia->aplic_addr == KVM_RISCV_AIA_UNDEF_ADDR)
+ return -EINVAL;
+
+ /* Initialize APLIC */
+ ret = kvm_riscv_aia_aplic_init(kvm);
+ if (ret)
+ return ret;
+
+ /* Iterate over each VCPU */
+ kvm_for_each_vcpu(idx, vcpu, kvm) {
+ vaia = &vcpu->arch.aia_context;
+
+ /* IMSIC base is required */
+ if (vaia->imsic_addr == KVM_RISCV_AIA_UNDEF_ADDR) {
+ ret = -EINVAL;
+ goto fail_cleanup_imsics;
+ }
+
+ /* All IMSICs should have matching base PPN */
+ if (base_ppn == KVM_RISCV_AIA_UNDEF_ADDR)
+ base_ppn = aia_imsic_ppn(aia, vaia->imsic_addr);
+ if (base_ppn != aia_imsic_ppn(aia, vaia->imsic_addr)) {
+ ret = -EINVAL;
+ goto fail_cleanup_imsics;
+ }
+
+ /* Update HART index of the IMSIC based on IMSIC base */
+ vaia->hart_index = aia_imsic_hart_index(aia,
+ vaia->imsic_addr);
+
+ /* Initialize IMSIC for this VCPU */
+ ret = kvm_riscv_vcpu_aia_imsic_init(vcpu);
+ if (ret)
+ goto fail_cleanup_imsics;
+ }
+
+ /* Set the initialized flag */
+ kvm->arch.aia.initialized = true;
+
+ return 0;
+
+fail_cleanup_imsics:
+ for (i = idx - 1; i >= 0; i--) {
+ vcpu = kvm_get_vcpu(kvm, i);
+ if (!vcpu)
+ continue;
+ kvm_riscv_vcpu_aia_imsic_cleanup(vcpu);
+ }
+ kvm_riscv_aia_aplic_cleanup(kvm);
+ return ret;
+}
+
+static int aia_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
+{
+ u32 nr;
+ u64 addr;
+ int nr_vcpus, r = -ENXIO;
+ unsigned long type = (unsigned long)attr->attr;
+ void __user *uaddr = (void __user *)(long)attr->addr;
+
+ switch (attr->group) {
+ case KVM_DEV_RISCV_AIA_GRP_CONFIG:
+ if (copy_from_user(&nr, uaddr, sizeof(nr)))
+ return -EFAULT;
+
+ mutex_lock(&dev->kvm->lock);
+ r = aia_config(dev->kvm, type, &nr, true);
+ mutex_unlock(&dev->kvm->lock);
+
+ break;
+
+ case KVM_DEV_RISCV_AIA_GRP_ADDR:
+ if (copy_from_user(&addr, uaddr, sizeof(addr)))
+ return -EFAULT;
+
+ nr_vcpus = atomic_read(&dev->kvm->online_vcpus);
+ mutex_lock(&dev->kvm->lock);
+ if (type == KVM_DEV_RISCV_AIA_ADDR_APLIC)
+ r = aia_aplic_addr(dev->kvm, &addr, true);
+ else if (type < KVM_DEV_RISCV_AIA_ADDR_IMSIC(nr_vcpus))
+ r = aia_imsic_addr(dev->kvm, &addr,
+ type - KVM_DEV_RISCV_AIA_ADDR_IMSIC(0), true);
+ mutex_unlock(&dev->kvm->lock);
+
+ break;
+
+ case KVM_DEV_RISCV_AIA_GRP_CTRL:
+ switch (type) {
+ case KVM_DEV_RISCV_AIA_CTRL_INIT:
+ mutex_lock(&dev->kvm->lock);
+ r = aia_init(dev->kvm);
+ mutex_unlock(&dev->kvm->lock);
+ break;
+ }
+
+ break;
+ }
+
+ return r;
+}
+
+static int aia_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
+{
+ u32 nr;
+ u64 addr;
+ int nr_vcpus, r = -ENXIO;
+ void __user *uaddr = (void __user *)(long)attr->addr;
+ unsigned long type = (unsigned long)attr->attr;
+
+ switch (attr->group) {
+ case KVM_DEV_RISCV_AIA_GRP_CONFIG:
+ if (copy_from_user(&nr, uaddr, sizeof(nr)))
+ return -EFAULT;
+
+ mutex_lock(&dev->kvm->lock);
+ r = aia_config(dev->kvm, type, &nr, false);
+ mutex_unlock(&dev->kvm->lock);
+ if (r)
+ return r;
+
+ if (copy_to_user(uaddr, &nr, sizeof(nr)))
+ return -EFAULT;
+
+ break;
+ case KVM_DEV_RISCV_AIA_GRP_ADDR:
+ if (copy_from_user(&addr, uaddr, sizeof(addr)))
+ return -EFAULT;
+
+ nr_vcpus = atomic_read(&dev->kvm->online_vcpus);
+ mutex_lock(&dev->kvm->lock);
+ if (type == KVM_DEV_RISCV_AIA_ADDR_APLIC)
+ r = aia_aplic_addr(dev->kvm, &addr, false);
+ else if (type < KVM_DEV_RISCV_AIA_ADDR_IMSIC(nr_vcpus))
+ r = aia_imsic_addr(dev->kvm, &addr,
+ type - KVM_DEV_RISCV_AIA_ADDR_IMSIC(0), false);
+ mutex_unlock(&dev->kvm->lock);
+ if (r)
+ return r;
+
+ if (copy_to_user(uaddr, &addr, sizeof(addr)))
+ return -EFAULT;
+
+ break;
+ }
+
+ return r;
+}
+
+static int aia_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
+{
+ int nr_vcpus;
+
+ switch (attr->group) {
+ case KVM_DEV_RISCV_AIA_GRP_CONFIG:
+ switch (attr->attr) {
+ case KVM_DEV_RISCV_AIA_CONFIG_MODE:
+ case KVM_DEV_RISCV_AIA_CONFIG_IDS:
+ case KVM_DEV_RISCV_AIA_CONFIG_SRCS:
+ case KVM_DEV_RISCV_AIA_CONFIG_GROUP_BITS:
+ case KVM_DEV_RISCV_AIA_CONFIG_GROUP_SHIFT:
+ case KVM_DEV_RISCV_AIA_CONFIG_HART_BITS:
+ case KVM_DEV_RISCV_AIA_CONFIG_GUEST_BITS:
+ return 0;
+ }
+ break;
+ case KVM_DEV_RISCV_AIA_GRP_ADDR:
+ nr_vcpus = atomic_read(&dev->kvm->online_vcpus);
+ if (attr->attr == KVM_DEV_RISCV_AIA_ADDR_APLIC)
+ return 0;
+ else if (attr->attr < KVM_DEV_RISCV_AIA_ADDR_IMSIC(nr_vcpus))
+ return 0;
+ break;
+ case KVM_DEV_RISCV_AIA_GRP_CTRL:
+ switch (attr->attr) {
+ case KVM_DEV_RISCV_AIA_CTRL_INIT:
+ return 0;
+ }
+ break;
+ }
+
+ return -ENXIO;
+}
+
+struct kvm_device_ops kvm_riscv_aia_device_ops = {
+ .name = "kvm-riscv-aia",
+ .create = aia_create,
+ .destroy = aia_destroy,
+ .set_attr = aia_set_attr,
+ .get_attr = aia_get_attr,
+ .has_attr = aia_has_attr,
+};
+
+int kvm_riscv_vcpu_aia_update(struct kvm_vcpu *vcpu)
+{
+ /* Proceed only if AIA was initialized successfully */
+ if (!kvm_riscv_aia_initialized(vcpu->kvm))
+ return 1;
+
+ /* Update the IMSIC HW state before entering guest mode */
+ return kvm_riscv_vcpu_aia_imsic_update(vcpu);
+}
+
+void kvm_riscv_vcpu_aia_reset(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_aia_csr *csr = &vcpu->arch.aia_context.guest_csr;
+ struct kvm_vcpu_aia_csr *reset_csr =
+ &vcpu->arch.aia_context.guest_reset_csr;
+
+ if (!kvm_riscv_aia_available())
+ return;
+ memcpy(csr, reset_csr, sizeof(*csr));
+
+ /* Proceed only if AIA was initialized successfully */
+ if (!kvm_riscv_aia_initialized(vcpu->kvm))
+ return;
+
+ /* Reset the IMSIC context */
+ kvm_riscv_vcpu_aia_imsic_reset(vcpu);
+}
+
+int kvm_riscv_vcpu_aia_init(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_aia *vaia = &vcpu->arch.aia_context;
+
+ if (!kvm_riscv_aia_available())
+ return 0;
+
+ /*
+ * We don't do any memory allocations over here because these
+ * will be done after AIA device is initialized by the user-space.
+ *
+ * Refer, aia_init() implementation for more details.
+ */
+
+ /* Initialize default values in AIA vcpu context */
+ vaia->imsic_addr = KVM_RISCV_AIA_UNDEF_ADDR;
+ vaia->hart_index = vcpu->vcpu_idx;
+
+ return 0;
+}
+
+void kvm_riscv_vcpu_aia_deinit(struct kvm_vcpu *vcpu)
+{
+ /* Proceed only if AIA was initialized successfully */
+ if (!kvm_riscv_aia_initialized(vcpu->kvm))
+ return;
+
+ /* Cleanup IMSIC context */
+ kvm_riscv_vcpu_aia_imsic_cleanup(vcpu);
+}
+
+int kvm_riscv_aia_inject_msi_by_id(struct kvm *kvm, u32 hart_index,
+ u32 guest_index, u32 iid)
+{
+ unsigned long idx;
+ struct kvm_vcpu *vcpu;
+
+ /* Proceed only if AIA was initialized successfully */
+ if (!kvm_riscv_aia_initialized(kvm))
+ return -EBUSY;
+
+ /* Inject MSI to matching VCPU */
+ kvm_for_each_vcpu(idx, vcpu, kvm) {
+ if (vcpu->arch.aia_context.hart_index == hart_index)
+ return kvm_riscv_vcpu_aia_imsic_inject(vcpu,
+ guest_index,
+ 0, iid);
+ }
+
+ return 0;
+}
+
+int kvm_riscv_aia_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
+{
+ gpa_t tppn, ippn;
+ unsigned long idx;
+ struct kvm_vcpu *vcpu;
+ u32 g, toff, iid = msi->data;
+ struct kvm_aia *aia = &kvm->arch.aia;
+ gpa_t target = (((gpa_t)msi->address_hi) << 32) | msi->address_lo;
+
+ /* Proceed only if AIA was initialized successfully */
+ if (!kvm_riscv_aia_initialized(kvm))
+ return -EBUSY;
+
+ /* Convert target address to target PPN */
+ tppn = target >> IMSIC_MMIO_PAGE_SHIFT;
+
+ /* Extract and clear Guest ID from target PPN */
+ g = tppn & (BIT(aia->nr_guest_bits) - 1);
+ tppn &= ~((gpa_t)(BIT(aia->nr_guest_bits) - 1));
+
+ /* Inject MSI to matching VCPU */
+ kvm_for_each_vcpu(idx, vcpu, kvm) {
+ ippn = vcpu->arch.aia_context.imsic_addr >>
+ IMSIC_MMIO_PAGE_SHIFT;
+ if (ippn == tppn) {
+ toff = target & (IMSIC_MMIO_PAGE_SZ - 1);
+ return kvm_riscv_vcpu_aia_imsic_inject(vcpu, g,
+ toff, iid);
+ }
+ }
+
+ return 0;
+}
+
+int kvm_riscv_aia_inject_irq(struct kvm *kvm, unsigned int irq, bool level)
+{
+ /* Proceed only if AIA was initialized successfully */
+ if (!kvm_riscv_aia_initialized(kvm))
+ return -EBUSY;
+
+ /* Inject interrupt level change in APLIC */
+ return kvm_riscv_aia_aplic_inject(kvm, irq, level);
+}
+
+void kvm_riscv_aia_init_vm(struct kvm *kvm)
+{
+ struct kvm_aia *aia = &kvm->arch.aia;
+
+ if (!kvm_riscv_aia_available())
+ return;
+
+ /*
+ * We don't do any memory allocations over here because these
+ * will be done after AIA device is initialized by the user-space.
+ *
+ * Refer, aia_init() implementation for more details.
+ */
+
+ /* Initialize default values in AIA global context */
+ aia->mode = (kvm_riscv_aia_nr_hgei) ?
+ KVM_DEV_RISCV_AIA_MODE_AUTO : KVM_DEV_RISCV_AIA_MODE_EMUL;
+ aia->nr_ids = kvm_riscv_aia_max_ids - 1;
+ aia->nr_sources = 0;
+ aia->nr_group_bits = 0;
+ aia->nr_group_shift = KVM_DEV_RISCV_AIA_GROUP_SHIFT_MIN;
+ aia->nr_hart_bits = 0;
+ aia->nr_guest_bits = 0;
+ aia->aplic_addr = KVM_RISCV_AIA_UNDEF_ADDR;
+}
+
+void kvm_riscv_aia_destroy_vm(struct kvm *kvm)
+{
+ /* Proceed only if AIA was initialized successfully */
+ if (!kvm_riscv_aia_initialized(kvm))
+ return;
+
+ /* Cleanup APLIC context */
+ kvm_riscv_aia_aplic_cleanup(kvm);
+}
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 737318b1c1d9..27ccd07898e1 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1442,6 +1442,8 @@ enum kvm_device_type {
#define KVM_DEV_TYPE_XIVE KVM_DEV_TYPE_XIVE
KVM_DEV_TYPE_ARM_PV_TIME,
#define KVM_DEV_TYPE_ARM_PV_TIME KVM_DEV_TYPE_ARM_PV_TIME
+ KVM_DEV_TYPE_RISCV_AIA,
+#define KVM_DEV_TYPE_RISCV_AIA KVM_DEV_TYPE_RISCV_AIA
KVM_DEV_TYPE_MAX,
};

--
2.34.1

2023-06-15 08:15:45

by Anup Patel

Subject: [PATCH v3 09/10] RISC-V: KVM: Add in-kernel virtualization of AIA IMSIC

We can have AIA IMSIC support for both HS-level and VS-level but
the VS-level IMSICs are optional. We use the VS-level IMSICs for
Guest/VM whenever available otherwise we fallback to software
emulation of AIA IMSIC.

This patch adds in-kernel virtualization of AIA IMSIC.

Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Atish Patra <[email protected]>
---
arch/riscv/include/asm/kvm_aia.h | 46 +-
arch/riscv/kvm/Makefile | 1 +
arch/riscv/kvm/aia_imsic.c | 913 +++++++++++++++++++++++++++++++
3 files changed, 924 insertions(+), 36 deletions(-)
create mode 100644 arch/riscv/kvm/aia_imsic.c

diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
index ba939c0054aa..a4f6ebf90e31 100644
--- a/arch/riscv/include/asm/kvm_aia.h
+++ b/arch/riscv/include/asm/kvm_aia.h
@@ -90,44 +90,18 @@ DECLARE_STATIC_KEY_FALSE(kvm_riscv_aia_available);

extern struct kvm_device_ops kvm_riscv_aia_device_ops;

-static inline void kvm_riscv_vcpu_aia_imsic_release(struct kvm_vcpu *vcpu)
-{
-}
-
-static inline int kvm_riscv_vcpu_aia_imsic_update(struct kvm_vcpu *vcpu)
-{
- return 1;
-}
+void kvm_riscv_vcpu_aia_imsic_release(struct kvm_vcpu *vcpu);
+int kvm_riscv_vcpu_aia_imsic_update(struct kvm_vcpu *vcpu);

#define KVM_RISCV_AIA_IMSIC_TOPEI (ISELECT_MASK + 1)
-static inline int kvm_riscv_vcpu_aia_imsic_rmw(struct kvm_vcpu *vcpu,
- unsigned long isel,
- unsigned long *val,
- unsigned long new_val,
- unsigned long wr_mask)
-{
- return 0;
-}
-
-static inline void kvm_riscv_vcpu_aia_imsic_reset(struct kvm_vcpu *vcpu)
-{
-}
-
-static inline int kvm_riscv_vcpu_aia_imsic_inject(struct kvm_vcpu *vcpu,
- u32 guest_index, u32 offset,
- u32 iid)
-{
- return 0;
-}
-
-static inline int kvm_riscv_vcpu_aia_imsic_init(struct kvm_vcpu *vcpu)
-{
- return 0;
-}
-
-static inline void kvm_riscv_vcpu_aia_imsic_cleanup(struct kvm_vcpu *vcpu)
-{
-}
+int kvm_riscv_vcpu_aia_imsic_rmw(struct kvm_vcpu *vcpu, unsigned long isel,
+ unsigned long *val, unsigned long new_val,
+ unsigned long wr_mask);
+void kvm_riscv_vcpu_aia_imsic_reset(struct kvm_vcpu *vcpu);
+int kvm_riscv_vcpu_aia_imsic_inject(struct kvm_vcpu *vcpu,
+ u32 guest_index, u32 offset, u32 iid);
+int kvm_riscv_vcpu_aia_imsic_init(struct kvm_vcpu *vcpu);
+void kvm_riscv_vcpu_aia_imsic_cleanup(struct kvm_vcpu *vcpu);

int kvm_riscv_aia_aplic_set_attr(struct kvm *kvm, unsigned long type, u32 v);
int kvm_riscv_aia_aplic_get_attr(struct kvm *kvm, unsigned long type, u32 *v);
diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile
index 94c43702c765..c1d1356387ff 100644
--- a/arch/riscv/kvm/Makefile
+++ b/arch/riscv/kvm/Makefile
@@ -29,3 +29,4 @@ kvm-$(CONFIG_RISCV_PMU_SBI) += vcpu_pmu.o vcpu_sbi_pmu.o
kvm-y += aia.o
kvm-y += aia_device.o
kvm-y += aia_aplic.o
+kvm-y += aia_imsic.o
diff --git a/arch/riscv/kvm/aia_imsic.c b/arch/riscv/kvm/aia_imsic.c
new file mode 100644
index 000000000000..2dc09dcb8ab5
--- /dev/null
+++ b/arch/riscv/kvm/aia_imsic.c
@@ -0,0 +1,913 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ * Copyright (C) 2022 Ventana Micro Systems Inc.
+ *
+ * Authors:
+ * Anup Patel <[email protected]>
+ */
+
+#include <linux/bitmap.h>
+#include <linux/kvm_host.h>
+#include <linux/math.h>
+#include <linux/spinlock.h>
+#include <linux/swab.h>
+#include <kvm/iodev.h>
+#include <asm/csr.h>
+#include <asm/kvm_aia_imsic.h>
+
+#define IMSIC_MAX_EIX (IMSIC_MAX_ID / BITS_PER_TYPE(u64))
+
+struct imsic_mrif_eix {
+ unsigned long eip[BITS_PER_TYPE(u64) / BITS_PER_LONG];
+ unsigned long eie[BITS_PER_TYPE(u64) / BITS_PER_LONG];
+};
+
+struct imsic_mrif {
+ struct imsic_mrif_eix eix[IMSIC_MAX_EIX];
+ unsigned long eithreshold;
+ unsigned long eidelivery;
+};
+
+struct imsic {
+ struct kvm_io_device iodev;
+
+ u32 nr_msis;
+ u32 nr_eix;
+ u32 nr_hw_eix;
+
+ /*
+ * At any point in time, the register state is in
+ * one of the following places:
+ *
+ * 1) Hardware: IMSIC VS-file (vsfile_cpu >= 0)
+ * 2) Software: IMSIC SW-file (vsfile_cpu < 0)
+ */
+
+ /* IMSIC VS-file */
+ rwlock_t vsfile_lock;
+ int vsfile_cpu;
+ int vsfile_hgei;
+ void __iomem *vsfile_va;
+ phys_addr_t vsfile_pa;
+
+ /* IMSIC SW-file */
+ struct imsic_mrif *swfile;
+ phys_addr_t swfile_pa;
+};
+
+#define imsic_vs_csr_read(__c) \
+({ \
+ unsigned long __r; \
+ csr_write(CSR_VSISELECT, __c); \
+ __r = csr_read(CSR_VSIREG); \
+ __r; \
+})
+
+#define imsic_read_switchcase(__ireg) \
+ case __ireg: \
+ return imsic_vs_csr_read(__ireg);
+#define imsic_read_switchcase_2(__ireg) \
+ imsic_read_switchcase(__ireg + 0) \
+ imsic_read_switchcase(__ireg + 1)
+#define imsic_read_switchcase_4(__ireg) \
+ imsic_read_switchcase_2(__ireg + 0) \
+ imsic_read_switchcase_2(__ireg + 2)
+#define imsic_read_switchcase_8(__ireg) \
+ imsic_read_switchcase_4(__ireg + 0) \
+ imsic_read_switchcase_4(__ireg + 4)
+#define imsic_read_switchcase_16(__ireg) \
+ imsic_read_switchcase_8(__ireg + 0) \
+ imsic_read_switchcase_8(__ireg + 8)
+#define imsic_read_switchcase_32(__ireg) \
+ imsic_read_switchcase_16(__ireg + 0) \
+ imsic_read_switchcase_16(__ireg + 16)
+#define imsic_read_switchcase_64(__ireg) \
+ imsic_read_switchcase_32(__ireg + 0) \
+ imsic_read_switchcase_32(__ireg + 32)
+
+static unsigned long imsic_eix_read(int ireg)
+{
+ switch (ireg) {
+ imsic_read_switchcase_64(IMSIC_EIP0)
+ imsic_read_switchcase_64(IMSIC_EIE0)
+ };
+
+ return 0;
+}
+
+#define imsic_vs_csr_swap(__c, __v) \
+({ \
+ unsigned long __r; \
+ csr_write(CSR_VSISELECT, __c); \
+ __r = csr_swap(CSR_VSIREG, __v); \
+ __r; \
+})
+
+#define imsic_swap_switchcase(__ireg, __v) \
+ case __ireg: \
+ return imsic_vs_csr_swap(__ireg, __v);
+#define imsic_swap_switchcase_2(__ireg, __v) \
+ imsic_swap_switchcase(__ireg + 0, __v) \
+ imsic_swap_switchcase(__ireg + 1, __v)
+#define imsic_swap_switchcase_4(__ireg, __v) \
+ imsic_swap_switchcase_2(__ireg + 0, __v) \
+ imsic_swap_switchcase_2(__ireg + 2, __v)
+#define imsic_swap_switchcase_8(__ireg, __v) \
+ imsic_swap_switchcase_4(__ireg + 0, __v) \
+ imsic_swap_switchcase_4(__ireg + 4, __v)
+#define imsic_swap_switchcase_16(__ireg, __v) \
+ imsic_swap_switchcase_8(__ireg + 0, __v) \
+ imsic_swap_switchcase_8(__ireg + 8, __v)
+#define imsic_swap_switchcase_32(__ireg, __v) \
+ imsic_swap_switchcase_16(__ireg + 0, __v) \
+ imsic_swap_switchcase_16(__ireg + 16, __v)
+#define imsic_swap_switchcase_64(__ireg, __v) \
+ imsic_swap_switchcase_32(__ireg + 0, __v) \
+ imsic_swap_switchcase_32(__ireg + 32, __v)
+
+static unsigned long imsic_eix_swap(int ireg, unsigned long val)
+{
+ switch (ireg) {
+ imsic_swap_switchcase_64(IMSIC_EIP0, val)
+ imsic_swap_switchcase_64(IMSIC_EIE0, val)
+ };
+
+ return 0;
+}
+
+#define imsic_vs_csr_write(__c, __v) \
+do { \
+ csr_write(CSR_VSISELECT, __c); \
+ csr_write(CSR_VSIREG, __v); \
+} while (0)
+
+#define imsic_write_switchcase(__ireg, __v) \
+ case __ireg: \
+ imsic_vs_csr_write(__ireg, __v); \
+ break;
+#define imsic_write_switchcase_2(__ireg, __v) \
+ imsic_write_switchcase(__ireg + 0, __v) \
+ imsic_write_switchcase(__ireg + 1, __v)
+#define imsic_write_switchcase_4(__ireg, __v) \
+ imsic_write_switchcase_2(__ireg + 0, __v) \
+ imsic_write_switchcase_2(__ireg + 2, __v)
+#define imsic_write_switchcase_8(__ireg, __v) \
+ imsic_write_switchcase_4(__ireg + 0, __v) \
+ imsic_write_switchcase_4(__ireg + 4, __v)
+#define imsic_write_switchcase_16(__ireg, __v) \
+ imsic_write_switchcase_8(__ireg + 0, __v) \
+ imsic_write_switchcase_8(__ireg + 8, __v)
+#define imsic_write_switchcase_32(__ireg, __v) \
+ imsic_write_switchcase_16(__ireg + 0, __v) \
+ imsic_write_switchcase_16(__ireg + 16, __v)
+#define imsic_write_switchcase_64(__ireg, __v) \
+ imsic_write_switchcase_32(__ireg + 0, __v) \
+ imsic_write_switchcase_32(__ireg + 32, __v)
+
+static void imsic_eix_write(int ireg, unsigned long val)
+{
+ switch (ireg) {
+ imsic_write_switchcase_64(IMSIC_EIP0, val)
+ imsic_write_switchcase_64(IMSIC_EIE0, val)
+ };
+}
+
+#define imsic_vs_csr_set(__c, __v) \
+do { \
+ csr_write(CSR_VSISELECT, __c); \
+ csr_set(CSR_VSIREG, __v); \
+} while (0)
+
+#define imsic_set_switchcase(__ireg, __v) \
+ case __ireg: \
+ imsic_vs_csr_set(__ireg, __v); \
+ break;
+#define imsic_set_switchcase_2(__ireg, __v) \
+ imsic_set_switchcase(__ireg + 0, __v) \
+ imsic_set_switchcase(__ireg + 1, __v)
+#define imsic_set_switchcase_4(__ireg, __v) \
+ imsic_set_switchcase_2(__ireg + 0, __v) \
+ imsic_set_switchcase_2(__ireg + 2, __v)
+#define imsic_set_switchcase_8(__ireg, __v) \
+ imsic_set_switchcase_4(__ireg + 0, __v) \
+ imsic_set_switchcase_4(__ireg + 4, __v)
+#define imsic_set_switchcase_16(__ireg, __v) \
+ imsic_set_switchcase_8(__ireg + 0, __v) \
+ imsic_set_switchcase_8(__ireg + 8, __v)
+#define imsic_set_switchcase_32(__ireg, __v) \
+ imsic_set_switchcase_16(__ireg + 0, __v) \
+ imsic_set_switchcase_16(__ireg + 16, __v)
+#define imsic_set_switchcase_64(__ireg, __v) \
+ imsic_set_switchcase_32(__ireg + 0, __v) \
+ imsic_set_switchcase_32(__ireg + 32, __v)
+
+static void imsic_eix_set(int ireg, unsigned long val)
+{
+ switch (ireg) {
+ imsic_set_switchcase_64(IMSIC_EIP0, val)
+ imsic_set_switchcase_64(IMSIC_EIE0, val)
+ };
+}
+
+static unsigned long imsic_mrif_atomic_rmw(struct imsic_mrif *mrif,
+ unsigned long *ptr,
+ unsigned long new_val,
+ unsigned long wr_mask)
+{
+ unsigned long old_val = 0, tmp = 0;
+
+ __asm__ __volatile__ (
+ "0: lr.w.aq %1, %0\n"
+ " and %2, %1, %3\n"
+ " or %2, %2, %4\n"
+ " sc.w.rl %2, %2, %0\n"
+ " bnez %2, 0b"
+ : "+A" (*ptr), "+r" (old_val), "+r" (tmp)
+ : "r" (~wr_mask), "r" (new_val & wr_mask)
+ : "memory");
+
+ return old_val;
+}
+
+static unsigned long imsic_mrif_atomic_or(struct imsic_mrif *mrif,
+ unsigned long *ptr,
+ unsigned long val)
+{
+ return arch_atomic_long_fetch_or(val, (atomic_long_t *)ptr);
+}
+
+#define imsic_mrif_atomic_write(__mrif, __ptr, __new_val) \
+ imsic_mrif_atomic_rmw(__mrif, __ptr, __new_val, -1UL)
+#define imsic_mrif_atomic_read(__mrif, __ptr) \
+ imsic_mrif_atomic_or(__mrif, __ptr, 0)
+
+static u32 imsic_mrif_topei(struct imsic_mrif *mrif, u32 nr_eix, u32 nr_msis)
+{
+ struct imsic_mrif_eix *eix;
+ u32 i, imin, imax, ei, max_msi;
+ unsigned long eipend[BITS_PER_TYPE(u64) / BITS_PER_LONG];
+ unsigned long eithreshold = imsic_mrif_atomic_read(mrif,
+ &mrif->eithreshold);
+
+ max_msi = (eithreshold && (eithreshold <= nr_msis)) ?
+ eithreshold : nr_msis;
+ for (ei = 0; ei < nr_eix; ei++) {
+ eix = &mrif->eix[ei];
+ eipend[0] = imsic_mrif_atomic_read(mrif, &eix->eie[0]) &
+ imsic_mrif_atomic_read(mrif, &eix->eip[0]);
+#ifdef CONFIG_32BIT
+ eipend[1] = imsic_mrif_atomic_read(mrif, &eix->eie[1]) &
+ imsic_mrif_atomic_read(mrif, &eix->eip[1]);
+ if (!eipend[0] && !eipend[1])
+#else
+ if (!eipend[0])
+#endif
+ continue;
+
+ imin = ei * BITS_PER_TYPE(u64);
+ imax = ((imin + BITS_PER_TYPE(u64)) < max_msi) ?
+ imin + BITS_PER_TYPE(u64) : max_msi;
+ for (i = (!imin) ? 1 : imin; i < imax; i++) {
+ if (test_bit(i - imin, eipend))
+ return (i << TOPEI_ID_SHIFT) | i;
+ }
+ }
+
+ return 0;
+}
+
+static int imsic_mrif_rmw(struct imsic_mrif *mrif, u32 nr_eix,
+ unsigned long isel, unsigned long *val,
+ unsigned long new_val, unsigned long wr_mask)
+{
+ bool pend;
+ struct imsic_mrif_eix *eix;
+ unsigned long *ei, num, old_val = 0;
+
+ switch (isel) {
+ case IMSIC_EIDELIVERY:
+ old_val = imsic_mrif_atomic_rmw(mrif, &mrif->eidelivery,
+ new_val, wr_mask & 0x1);
+ break;
+ case IMSIC_EITHRESHOLD:
+ old_val = imsic_mrif_atomic_rmw(mrif, &mrif->eithreshold,
+ new_val, wr_mask & (IMSIC_MAX_ID - 1));
+ break;
+ case IMSIC_EIP0 ... IMSIC_EIP63:
+ case IMSIC_EIE0 ... IMSIC_EIE63:
+ if (isel >= IMSIC_EIP0 && isel <= IMSIC_EIP63) {
+ pend = true;
+ num = isel - IMSIC_EIP0;
+ } else {
+ pend = false;
+ num = isel - IMSIC_EIE0;
+ }
+
+ if ((num / 2) >= nr_eix)
+ return -EINVAL;
+ eix = &mrif->eix[num / 2];
+
+#ifndef CONFIG_32BIT
+ if (num & 0x1)
+ return -EINVAL;
+ ei = (pend) ? &eix->eip[0] : &eix->eie[0];
+#else
+ ei = (pend) ? &eix->eip[num & 0x1] : &eix->eie[num & 0x1];
+#endif
+
+ /* Bit0 of EIP0 or EIE0 is read-only */
+ if (!num)
+ wr_mask &= ~BIT(0);
+
+ old_val = imsic_mrif_atomic_rmw(mrif, ei, new_val, wr_mask);
+ break;
+ default:
+ return -ENOENT;
+ };
+
+ if (val)
+ *val = old_val;
+
+ return 0;
+}
+
+struct imsic_vsfile_read_data {
+ int hgei;
+ u32 nr_eix;
+ bool clear;
+ struct imsic_mrif *mrif;
+};
+
+static void imsic_vsfile_local_read(void *data)
+{
+ u32 i;
+ struct imsic_mrif_eix *eix;
+ struct imsic_vsfile_read_data *idata = data;
+ struct imsic_mrif *mrif = idata->mrif;
+ unsigned long new_hstatus, old_hstatus, old_vsiselect;
+
+ old_vsiselect = csr_read(CSR_VSISELECT);
+ old_hstatus = csr_read(CSR_HSTATUS);
+ new_hstatus = old_hstatus & ~HSTATUS_VGEIN;
+ new_hstatus |= ((unsigned long)idata->hgei) << HSTATUS_VGEIN_SHIFT;
+ csr_write(CSR_HSTATUS, new_hstatus);
+
+ /*
+ * We don't use imsic_mrif_atomic_xyz() functions to store
+ * values in MRIF because imsic_vsfile_read() is always called
+ * with pointer to temporary MRIF on stack.
+ */
+
+ if (idata->clear) {
+ mrif->eidelivery = imsic_vs_csr_swap(IMSIC_EIDELIVERY, 0);
+ mrif->eithreshold = imsic_vs_csr_swap(IMSIC_EITHRESHOLD, 0);
+ for (i = 0; i < idata->nr_eix; i++) {
+ eix = &mrif->eix[i];
+ eix->eip[0] = imsic_eix_swap(IMSIC_EIP0 + i * 2, 0);
+ eix->eie[0] = imsic_eix_swap(IMSIC_EIE0 + i * 2, 0);
+#ifdef CONFIG_32BIT
+ eix->eip[1] = imsic_eix_swap(IMSIC_EIP0 + i * 2 + 1, 0);
+ eix->eie[1] = imsic_eix_swap(IMSIC_EIE0 + i * 2 + 1, 0);
+#endif
+ }
+ } else {
+ mrif->eidelivery = imsic_vs_csr_read(IMSIC_EIDELIVERY);
+ mrif->eithreshold = imsic_vs_csr_read(IMSIC_EITHRESHOLD);
+ for (i = 0; i < idata->nr_eix; i++) {
+ eix = &mrif->eix[i];
+ eix->eip[0] = imsic_eix_read(IMSIC_EIP0 + i * 2);
+ eix->eie[0] = imsic_eix_read(IMSIC_EIE0 + i * 2);
+#ifdef CONFIG_32BIT
+ eix->eip[1] = imsic_eix_read(IMSIC_EIP0 + i * 2 + 1);
+ eix->eie[1] = imsic_eix_read(IMSIC_EIE0 + i * 2 + 1);
+#endif
+ }
+ }
+
+ csr_write(CSR_HSTATUS, old_hstatus);
+ csr_write(CSR_VSISELECT, old_vsiselect);
+}
+
+static void imsic_vsfile_read(int vsfile_hgei, int vsfile_cpu, u32 nr_eix,
+ bool clear, struct imsic_mrif *mrif)
+{
+ struct imsic_vsfile_read_data idata;
+
+ /* We can only read clear if we have a IMSIC VS-file */
+ if (vsfile_cpu < 0 || vsfile_hgei <= 0)
+ return;
+
+ /* We can only read clear on local CPU */
+ idata.hgei = vsfile_hgei;
+ idata.nr_eix = nr_eix;
+ idata.clear = clear;
+ idata.mrif = mrif;
+ on_each_cpu_mask(cpumask_of(vsfile_cpu),
+ imsic_vsfile_local_read, &idata, 1);
+}
+
+static void imsic_vsfile_local_clear(int vsfile_hgei, u32 nr_eix)
+{
+ u32 i;
+ unsigned long new_hstatus, old_hstatus, old_vsiselect;
+
+ /* We can only zero-out if we have a IMSIC VS-file */
+ if (vsfile_hgei <= 0)
+ return;
+
+ old_vsiselect = csr_read(CSR_VSISELECT);
+ old_hstatus = csr_read(CSR_HSTATUS);
+ new_hstatus = old_hstatus & ~HSTATUS_VGEIN;
+ new_hstatus |= ((unsigned long)vsfile_hgei) << HSTATUS_VGEIN_SHIFT;
+ csr_write(CSR_HSTATUS, new_hstatus);
+
+ imsic_vs_csr_write(IMSIC_EIDELIVERY, 0);
+ imsic_vs_csr_write(IMSIC_EITHRESHOLD, 0);
+ for (i = 0; i < nr_eix; i++) {
+ imsic_eix_write(IMSIC_EIP0 + i * 2, 0);
+ imsic_eix_write(IMSIC_EIE0 + i * 2, 0);
+#ifdef CONFIG_32BIT
+ imsic_eix_write(IMSIC_EIP0 + i * 2 + 1, 0);
+ imsic_eix_write(IMSIC_EIE0 + i * 2 + 1, 0);
+#endif
+ }
+
+ csr_write(CSR_HSTATUS, old_hstatus);
+ csr_write(CSR_VSISELECT, old_vsiselect);
+}
+
+static void imsic_vsfile_local_update(int vsfile_hgei, u32 nr_eix,
+ struct imsic_mrif *mrif)
+{
+ u32 i;
+ struct imsic_mrif_eix *eix;
+ unsigned long new_hstatus, old_hstatus, old_vsiselect;
+
+ /* We can only update if we have a HW IMSIC context */
+ if (vsfile_hgei <= 0)
+ return;
+
+ /*
+ * We don't use imsic_mrif_atomic_xyz() functions to read values
+ * from MRIF in this function because it is always called with
+ * pointer to temporary MRIF on stack.
+ */
+
+ old_vsiselect = csr_read(CSR_VSISELECT);
+ old_hstatus = csr_read(CSR_HSTATUS);
+ new_hstatus = old_hstatus & ~HSTATUS_VGEIN;
+ new_hstatus |= ((unsigned long)vsfile_hgei) << HSTATUS_VGEIN_SHIFT;
+ csr_write(CSR_HSTATUS, new_hstatus);
+
+ for (i = 0; i < nr_eix; i++) {
+ eix = &mrif->eix[i];
+ imsic_eix_set(IMSIC_EIP0 + i * 2, eix->eip[0]);
+ imsic_eix_set(IMSIC_EIE0 + i * 2, eix->eie[0]);
+#ifdef CONFIG_32BIT
+ imsic_eix_set(IMSIC_EIP0 + i * 2 + 1, eix->eip[1]);
+ imsic_eix_set(IMSIC_EIE0 + i * 2 + 1, eix->eie[1]);
+#endif
+ }
+ imsic_vs_csr_write(IMSIC_EITHRESHOLD, mrif->eithreshold);
+ imsic_vs_csr_write(IMSIC_EIDELIVERY, mrif->eidelivery);
+
+ csr_write(CSR_HSTATUS, old_hstatus);
+ csr_write(CSR_VSISELECT, old_vsiselect);
+}
+
+static void imsic_vsfile_cleanup(struct imsic *imsic)
+{
+ int old_vsfile_hgei, old_vsfile_cpu;
+ unsigned long flags;
+
+ /*
+ * We don't use imsic_mrif_atomic_xyz() functions to clear the
+ * SW-file in this function because it is always called when the
+ * VCPU is being destroyed.
+ */
+
+ write_lock_irqsave(&imsic->vsfile_lock, flags);
+ old_vsfile_hgei = imsic->vsfile_hgei;
+ old_vsfile_cpu = imsic->vsfile_cpu;
+ imsic->vsfile_cpu = imsic->vsfile_hgei = -1;
+ imsic->vsfile_va = NULL;
+ imsic->vsfile_pa = 0;
+ write_unlock_irqrestore(&imsic->vsfile_lock, flags);
+
+ memset(imsic->swfile, 0, sizeof(*imsic->swfile));
+
+ if (old_vsfile_cpu >= 0)
+ kvm_riscv_aia_free_hgei(old_vsfile_cpu, old_vsfile_hgei);
+}
+
+static void imsic_swfile_extirq_update(struct kvm_vcpu *vcpu)
+{
+ struct imsic *imsic = vcpu->arch.aia_context.imsic_state;
+ struct imsic_mrif *mrif = imsic->swfile;
+
+ if (imsic_mrif_atomic_read(mrif, &mrif->eidelivery) &&
+ imsic_mrif_topei(mrif, imsic->nr_eix, imsic->nr_msis))
+ kvm_riscv_vcpu_set_interrupt(vcpu, IRQ_VS_EXT);
+ else
+ kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_EXT);
+}
+
+static void imsic_swfile_read(struct kvm_vcpu *vcpu, bool clear,
+ struct imsic_mrif *mrif)
+{
+ struct imsic *imsic = vcpu->arch.aia_context.imsic_state;
+
+ /*
+ * We don't use imsic_mrif_atomic_xyz() functions to read and
+ * write SW-file and MRIF in this function because it is always
+ * called when VCPU is not using SW-file and the MRIF points to
+ * a temporary MRIF on stack.
+ */
+
+ memcpy(mrif, imsic->swfile, sizeof(*mrif));
+ if (clear) {
+ memset(imsic->swfile, 0, sizeof(*imsic->swfile));
+ kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_EXT);
+ }
+}
+
+static void imsic_swfile_update(struct kvm_vcpu *vcpu,
+ struct imsic_mrif *mrif)
+{
+ u32 i;
+ struct imsic_mrif_eix *seix, *eix;
+ struct imsic *imsic = vcpu->arch.aia_context.imsic_state;
+ struct imsic_mrif *smrif = imsic->swfile;
+
+ imsic_mrif_atomic_write(smrif, &smrif->eidelivery, mrif->eidelivery);
+ imsic_mrif_atomic_write(smrif, &smrif->eithreshold, mrif->eithreshold);
+ for (i = 0; i < imsic->nr_eix; i++) {
+ seix = &smrif->eix[i];
+ eix = &mrif->eix[i];
+ imsic_mrif_atomic_or(smrif, &seix->eip[0], eix->eip[0]);
+ imsic_mrif_atomic_or(smrif, &seix->eie[0], eix->eie[0]);
+#ifdef CONFIG_32BIT
+ imsic_mrif_atomic_or(smrif, &seix->eip[1], eix->eip[1]);
+ imsic_mrif_atomic_or(smrif, &seix->eie[1], eix->eie[1]);
+#endif
+ }
+
+ imsic_swfile_extirq_update(vcpu);
+}
+
+void kvm_riscv_vcpu_aia_imsic_release(struct kvm_vcpu *vcpu)
+{
+ unsigned long flags;
+ struct imsic_mrif tmrif;
+ int old_vsfile_hgei, old_vsfile_cpu;
+ struct imsic *imsic = vcpu->arch.aia_context.imsic_state;
+
+ /* Read and clear IMSIC VS-file details */
+ write_lock_irqsave(&imsic->vsfile_lock, flags);
+ old_vsfile_hgei = imsic->vsfile_hgei;
+ old_vsfile_cpu = imsic->vsfile_cpu;
+ imsic->vsfile_cpu = imsic->vsfile_hgei = -1;
+ imsic->vsfile_va = NULL;
+ imsic->vsfile_pa = 0;
+ write_unlock_irqrestore(&imsic->vsfile_lock, flags);
+
+ /* Do nothing, if no IMSIC VS-file to release */
+ if (old_vsfile_cpu < 0)
+ return;
+
+ /*
+ * At this point, all interrupt producers are still using
+ * the old IMSIC VS-file so we first re-direct all interrupt
+ * producers.
+ */
+
+ /* Purge the G-stage mapping */
+ kvm_riscv_gstage_iounmap(vcpu->kvm,
+ vcpu->arch.aia_context.imsic_addr,
+ IMSIC_MMIO_PAGE_SZ);
+
+ /* TODO: Purge the IOMMU mapping ??? */
+
+ /*
+ * At this point, all interrupt producers have been re-directed
+ * to somewhere else so we move register state from the old IMSIC
+ * VS-file to the IMSIC SW-file.
+ */
+
+ /* Read and clear register state from old IMSIC VS-file */
+ memset(&tmrif, 0, sizeof(tmrif));
+ imsic_vsfile_read(old_vsfile_hgei, old_vsfile_cpu, imsic->nr_hw_eix,
+ true, &tmrif);
+
+ /* Update register state in IMSIC SW-file */
+ imsic_swfile_update(vcpu, &tmrif);
+
+ /* Free-up old IMSIC VS-file */
+ kvm_riscv_aia_free_hgei(old_vsfile_cpu, old_vsfile_hgei);
+}
+
+int kvm_riscv_vcpu_aia_imsic_update(struct kvm_vcpu *vcpu)
+{
+ unsigned long flags;
+ phys_addr_t new_vsfile_pa;
+ struct imsic_mrif tmrif;
+ void __iomem *new_vsfile_va;
+ struct kvm *kvm = vcpu->kvm;
+ struct kvm_run *run = vcpu->run;
+ struct kvm_vcpu_aia *vaia = &vcpu->arch.aia_context;
+ struct imsic *imsic = vaia->imsic_state;
+ int ret = 0, new_vsfile_hgei = -1, old_vsfile_hgei, old_vsfile_cpu;
+
+ /* Do nothing for emulation mode */
+ if (kvm->arch.aia.mode == KVM_DEV_RISCV_AIA_MODE_EMUL)
+ return 1;
+
+ /* Read old IMSIC VS-file details */
+ read_lock_irqsave(&imsic->vsfile_lock, flags);
+ old_vsfile_hgei = imsic->vsfile_hgei;
+ old_vsfile_cpu = imsic->vsfile_cpu;
+ read_unlock_irqrestore(&imsic->vsfile_lock, flags);
+
+ /* Do nothing if we are continuing on same CPU */
+ if (old_vsfile_cpu == vcpu->cpu)
+ return 1;
+
+ /* Allocate new IMSIC VS-file */
+ ret = kvm_riscv_aia_alloc_hgei(vcpu->cpu, vcpu,
+ &new_vsfile_va, &new_vsfile_pa);
+ if (ret <= 0) {
+ /* For HW acceleration mode, we can't continue */
+ if (kvm->arch.aia.mode == KVM_DEV_RISCV_AIA_MODE_HWACCEL) {
+ run->fail_entry.hardware_entry_failure_reason =
+ CSR_HSTATUS;
+ run->fail_entry.cpu = vcpu->cpu;
+ run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+ return 0;
+ }
+
+ /* Release old IMSIC VS-file */
+ if (old_vsfile_cpu >= 0)
+ kvm_riscv_vcpu_aia_imsic_release(vcpu);
+
+ /* For automatic mode, we continue */
+ goto done;
+ }
+ new_vsfile_hgei = ret;
+
+ /*
+ * At this point, all interrupt producers are still using
+ * to the old IMSIC VS-file so we first move all interrupt
+ * producers to the new IMSIC VS-file.
+ */
+
+ /* Zero-out new IMSIC VS-file */
+ imsic_vsfile_local_clear(new_vsfile_hgei, imsic->nr_hw_eix);
+
+ /* Update G-stage mapping for the new IMSIC VS-file */
+ ret = kvm_riscv_gstage_ioremap(kvm, vcpu->arch.aia_context.imsic_addr,
+ new_vsfile_pa, IMSIC_MMIO_PAGE_SZ,
+ true, true);
+ if (ret)
+ goto fail_free_vsfile_hgei;
+
+ /* TODO: Update the IOMMU mapping ??? */
+
+ /* Update new IMSIC VS-file details in IMSIC context */
+ write_lock_irqsave(&imsic->vsfile_lock, flags);
+ imsic->vsfile_hgei = new_vsfile_hgei;
+ imsic->vsfile_cpu = vcpu->cpu;
+ imsic->vsfile_va = new_vsfile_va;
+ imsic->vsfile_pa = new_vsfile_pa;
+ write_unlock_irqrestore(&imsic->vsfile_lock, flags);
+
+ /*
+ * At this point, all interrupt producers have been moved
+ * to the new IMSIC VS-file so we move register state from
+ * the old IMSIC VS/SW-file to the new IMSIC VS-file.
+ */
+
+ memset(&tmrif, 0, sizeof(tmrif));
+ if (old_vsfile_cpu >= 0) {
+ /* Read and clear register state from old IMSIC VS-file */
+ imsic_vsfile_read(old_vsfile_hgei, old_vsfile_cpu,
+ imsic->nr_hw_eix, true, &tmrif);
+
+ /* Free-up old IMSIC VS-file */
+ kvm_riscv_aia_free_hgei(old_vsfile_cpu, old_vsfile_hgei);
+ } else {
+ /* Read and clear register state from IMSIC SW-file */
+ imsic_swfile_read(vcpu, true, &tmrif);
+ }
+
+ /* Restore register state in the new IMSIC VS-file */
+ imsic_vsfile_local_update(new_vsfile_hgei, imsic->nr_hw_eix, &tmrif);
+
+done:
+ /* Set VCPU HSTATUS.VGEIN to new IMSIC VS-file */
+ vcpu->arch.guest_context.hstatus &= ~HSTATUS_VGEIN;
+ if (new_vsfile_hgei > 0)
+ vcpu->arch.guest_context.hstatus |=
+ ((unsigned long)new_vsfile_hgei) << HSTATUS_VGEIN_SHIFT;
+
+ /* Continue run-loop */
+ return 1;
+
+fail_free_vsfile_hgei:
+ kvm_riscv_aia_free_hgei(vcpu->cpu, new_vsfile_hgei);
+ return ret;
+}
+
+int kvm_riscv_vcpu_aia_imsic_rmw(struct kvm_vcpu *vcpu, unsigned long isel,
+ unsigned long *val, unsigned long new_val,
+ unsigned long wr_mask)
+{
+ u32 topei;
+ struct imsic_mrif_eix *eix;
+ int r, rc = KVM_INSN_CONTINUE_NEXT_SEPC;
+ struct imsic *imsic = vcpu->arch.aia_context.imsic_state;
+
+ if (isel == KVM_RISCV_AIA_IMSIC_TOPEI) {
+ /* Read pending and enabled interrupt with highest priority */
+ topei = imsic_mrif_topei(imsic->swfile, imsic->nr_eix,
+ imsic->nr_msis);
+ if (val)
+ *val = topei;
+
+ /* Writes ignore value and clear top pending interrupt */
+ if (topei && wr_mask) {
+ topei >>= TOPEI_ID_SHIFT;
+ if (topei) {
+ eix = &imsic->swfile->eix[topei /
+ BITS_PER_TYPE(u64)];
+ clear_bit(topei & (BITS_PER_TYPE(u64) - 1),
+ eix->eip);
+ }
+ }
+ } else {
+ r = imsic_mrif_rmw(imsic->swfile, imsic->nr_eix, isel,
+ val, new_val, wr_mask);
+ /* Forward unknown IMSIC register to user-space */
+ if (r)
+ rc = (r == -ENOENT) ? 0 : KVM_INSN_ILLEGAL_TRAP;
+ }
+
+ if (wr_mask)
+ imsic_swfile_extirq_update(vcpu);
+
+ return rc;
+}
+
+void kvm_riscv_vcpu_aia_imsic_reset(struct kvm_vcpu *vcpu)
+{
+ struct imsic *imsic = vcpu->arch.aia_context.imsic_state;
+
+ if (!imsic)
+ return;
+
+ kvm_riscv_vcpu_aia_imsic_release(vcpu);
+
+ memset(imsic->swfile, 0, sizeof(*imsic->swfile));
+}
+
+int kvm_riscv_vcpu_aia_imsic_inject(struct kvm_vcpu *vcpu,
+ u32 guest_index, u32 offset, u32 iid)
+{
+ unsigned long flags;
+ struct imsic_mrif_eix *eix;
+ struct imsic *imsic = vcpu->arch.aia_context.imsic_state;
+
+ /* We only emulate one IMSIC MMIO page for each Guest VCPU */
+ if (!imsic || !iid || guest_index ||
+ (offset != IMSIC_MMIO_SETIPNUM_LE &&
+ offset != IMSIC_MMIO_SETIPNUM_BE))
+ return -ENODEV;
+
+ iid = (offset == IMSIC_MMIO_SETIPNUM_BE) ? __swab32(iid) : iid;
+ if (imsic->nr_msis <= iid)
+ return -EINVAL;
+
+ read_lock_irqsave(&imsic->vsfile_lock, flags);
+
+ if (imsic->vsfile_cpu >= 0) {
+ writel(iid, imsic->vsfile_va + IMSIC_MMIO_SETIPNUM_LE);
+ kvm_vcpu_kick(vcpu);
+ } else {
+ eix = &imsic->swfile->eix[iid / BITS_PER_TYPE(u64)];
+ set_bit(iid & (BITS_PER_TYPE(u64) - 1), eix->eip);
+ imsic_swfile_extirq_update(vcpu);
+ }
+
+ read_unlock_irqrestore(&imsic->vsfile_lock, flags);
+
+ return 0;
+}
+
+static int imsic_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
+ gpa_t addr, int len, void *val)
+{
+ if (len != 4 || (addr & 0x3) != 0)
+ return -EOPNOTSUPP;
+
+ *((u32 *)val) = 0;
+
+ return 0;
+}
+
+static int imsic_mmio_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
+ gpa_t addr, int len, const void *val)
+{
+ struct kvm_msi msi = { 0 };
+
+ if (len != 4 || (addr & 0x3) != 0)
+ return -EOPNOTSUPP;
+
+ msi.address_hi = addr >> 32;
+ msi.address_lo = (u32)addr;
+ msi.data = *((const u32 *)val);
+ kvm_riscv_aia_inject_msi(vcpu->kvm, &msi);
+
+ return 0;
+};
+
+static struct kvm_io_device_ops imsic_iodoev_ops = {
+ .read = imsic_mmio_read,
+ .write = imsic_mmio_write,
+};
+
+int kvm_riscv_vcpu_aia_imsic_init(struct kvm_vcpu *vcpu)
+{
+ int ret = 0;
+ struct imsic *imsic;
+ struct page *swfile_page;
+ struct kvm *kvm = vcpu->kvm;
+
+ /* Fail if we have zero IDs */
+ if (!kvm->arch.aia.nr_ids)
+ return -EINVAL;
+
+ /* Allocate IMSIC context */
+ imsic = kzalloc(sizeof(*imsic), GFP_KERNEL);
+ if (!imsic)
+ return -ENOMEM;
+ vcpu->arch.aia_context.imsic_state = imsic;
+
+ /* Setup IMSIC context */
+ imsic->nr_msis = kvm->arch.aia.nr_ids + 1;
+ rwlock_init(&imsic->vsfile_lock);
+ imsic->nr_eix = BITS_TO_U64(imsic->nr_msis);
+ imsic->nr_hw_eix = BITS_TO_U64(kvm_riscv_aia_max_ids);
+ imsic->vsfile_hgei = imsic->vsfile_cpu = -1;
+
+ /* Setup IMSIC SW-file */
+ swfile_page = alloc_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(sizeof(*imsic->swfile)));
+ if (!swfile_page) {
+ ret = -ENOMEM;
+ goto fail_free_imsic;
+ }
+ imsic->swfile = page_to_virt(swfile_page);
+ imsic->swfile_pa = page_to_phys(swfile_page);
+
+ /* Setup IO device */
+ kvm_iodevice_init(&imsic->iodev, &imsic_iodoev_ops);
+ mutex_lock(&kvm->slots_lock);
+ ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS,
+ vcpu->arch.aia_context.imsic_addr,
+ KVM_DEV_RISCV_IMSIC_SIZE,
+ &imsic->iodev);
+ mutex_unlock(&kvm->slots_lock);
+ if (ret)
+ goto fail_free_swfile;
+
+ return 0;
+
+fail_free_swfile:
+ free_pages((unsigned long)imsic->swfile,
+ get_order(sizeof(*imsic->swfile)));
+fail_free_imsic:
+ vcpu->arch.aia_context.imsic_state = NULL;
+ kfree(imsic);
+ return ret;
+}
+
+void kvm_riscv_vcpu_aia_imsic_cleanup(struct kvm_vcpu *vcpu)
+{
+ struct kvm *kvm = vcpu->kvm;
+ struct imsic *imsic = vcpu->arch.aia_context.imsic_state;
+
+ if (!imsic)
+ return;
+
+ imsic_vsfile_cleanup(imsic);
+
+ mutex_lock(&kvm->slots_lock);
+ kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &imsic->iodev);
+ mutex_unlock(&kvm->slots_lock);
+
+ free_pages((unsigned long)imsic->swfile,
+ get_order(sizeof(*imsic->swfile)));
+
+ vcpu->arch.aia_context.imsic_state = NULL;
+ kfree(imsic);
+}
--
2.34.1

2023-06-15 08:18:02

by Anup Patel

Subject: [PATCH v3 10/10] RISC-V: KVM: Expose IMSIC registers as attributes of AIA irqchip

We expose IMSIC registers as KVM device attributes of the in-kernel
AIA irqchip device. This will allow KVM user-space to save/restore
IMISC state of each VCPU using KVM device ioctls().

Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Atish Patra <[email protected]>
---
arch/riscv/include/asm/kvm_aia.h | 3 +
arch/riscv/include/uapi/asm/kvm.h | 17 +++
arch/riscv/kvm/aia_device.c | 29 ++++-
arch/riscv/kvm/aia_imsic.c | 170 ++++++++++++++++++++++++++++++
4 files changed, 217 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
index a4f6ebf90e31..1f37b600ca47 100644
--- a/arch/riscv/include/asm/kvm_aia.h
+++ b/arch/riscv/include/asm/kvm_aia.h
@@ -97,6 +97,9 @@ int kvm_riscv_vcpu_aia_imsic_update(struct kvm_vcpu *vcpu);
int kvm_riscv_vcpu_aia_imsic_rmw(struct kvm_vcpu *vcpu, unsigned long isel,
unsigned long *val, unsigned long new_val,
unsigned long wr_mask);
+int kvm_riscv_aia_imsic_rw_attr(struct kvm *kvm, unsigned long type,
+ bool write, unsigned long *val);
+int kvm_riscv_aia_imsic_has_attr(struct kvm *kvm, unsigned long type);
void kvm_riscv_vcpu_aia_imsic_reset(struct kvm_vcpu *vcpu);
int kvm_riscv_vcpu_aia_imsic_inject(struct kvm_vcpu *vcpu,
u32 guest_index, u32 offset, u32 iid);
diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
index 9ed822fc5589..61d7fecc4899 100644
--- a/arch/riscv/include/uapi/asm/kvm.h
+++ b/arch/riscv/include/uapi/asm/kvm.h
@@ -255,6 +255,23 @@ enum KVM_RISCV_SBI_EXT_ID {
*/
#define KVM_DEV_RISCV_AIA_GRP_APLIC 3

+/*
+ * The lower 12-bits of the device attribute type contains the iselect
+ * value of the IMSIC register (range 0x70-0xFF) whereas the higher order
+ * bits contains the VCPU id.
+ */
+#define KVM_DEV_RISCV_AIA_GRP_IMSIC 4
+#define KVM_DEV_RISCV_AIA_IMSIC_ISEL_BITS 12
+#define KVM_DEV_RISCV_AIA_IMSIC_ISEL_MASK \
+ ((1U << KVM_DEV_RISCV_AIA_IMSIC_ISEL_BITS) - 1)
+#define KVM_DEV_RISCV_AIA_IMSIC_MKATTR(__vcpu, __isel) \
+ (((__vcpu) << KVM_DEV_RISCV_AIA_IMSIC_ISEL_BITS) | \
+ ((__isel) & KVM_DEV_RISCV_AIA_IMSIC_ISEL_MASK))
+#define KVM_DEV_RISCV_AIA_IMSIC_GET_ISEL(__attr) \
+ ((__attr) & KVM_DEV_RISCV_AIA_IMSIC_ISEL_MASK)
+#define KVM_DEV_RISCV_AIA_IMSIC_GET_VCPU(__attr) \
+ ((__attr) >> KVM_DEV_RISCV_AIA_IMSIC_ISEL_BITS)
+
/* One single KVM irqchip, ie. the AIA */
#define KVM_NR_IRQCHIPS 1

diff --git a/arch/riscv/kvm/aia_device.c b/arch/riscv/kvm/aia_device.c
index c649ad6e8e0a..84dae351b6d7 100644
--- a/arch/riscv/kvm/aia_device.c
+++ b/arch/riscv/kvm/aia_device.c
@@ -327,7 +327,7 @@ static int aia_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
u32 nr;
u64 addr;
int nr_vcpus, r = -ENXIO;
- unsigned long type = (unsigned long)attr->attr;
+ unsigned long v, type = (unsigned long)attr->attr;
void __user *uaddr = (void __user *)(long)attr->addr;

switch (attr->group) {
@@ -374,6 +374,15 @@ static int aia_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
r = kvm_riscv_aia_aplic_set_attr(dev->kvm, type, nr);
mutex_unlock(&dev->kvm->lock);

+ break;
+ case KVM_DEV_RISCV_AIA_GRP_IMSIC:
+ if (copy_from_user(&v, uaddr, sizeof(v)))
+ return -EFAULT;
+
+ mutex_lock(&dev->kvm->lock);
+ r = kvm_riscv_aia_imsic_rw_attr(dev->kvm, type, true, &v);
+ mutex_unlock(&dev->kvm->lock);
+
break;
}

@@ -386,7 +395,7 @@ static int aia_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
u64 addr;
int nr_vcpus, r = -ENXIO;
void __user *uaddr = (void __user *)(long)attr->addr;
- unsigned long type = (unsigned long)attr->attr;
+ unsigned long v, type = (unsigned long)attr->attr;

switch (attr->group) {
case KVM_DEV_RISCV_AIA_GRP_CONFIG:
@@ -435,6 +444,20 @@ static int aia_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
if (copy_to_user(uaddr, &nr, sizeof(nr)))
return -EFAULT;

+ break;
+ case KVM_DEV_RISCV_AIA_GRP_IMSIC:
+ if (copy_from_user(&v, uaddr, sizeof(v)))
+ return -EFAULT;
+
+ mutex_lock(&dev->kvm->lock);
+ r = kvm_riscv_aia_imsic_rw_attr(dev->kvm, type, false, &v);
+ mutex_unlock(&dev->kvm->lock);
+ if (r)
+ return r;
+
+ if (copy_to_user(uaddr, &v, sizeof(v)))
+ return -EFAULT;
+
break;
}

@@ -473,6 +496,8 @@ static int aia_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
break;
case KVM_DEV_RISCV_AIA_GRP_APLIC:
return kvm_riscv_aia_aplic_has_attr(dev->kvm, attr->attr);
+ case KVM_DEV_RISCV_AIA_GRP_IMSIC:
+ return kvm_riscv_aia_imsic_has_attr(dev->kvm, attr->attr);
}

return -ENXIO;
diff --git a/arch/riscv/kvm/aia_imsic.c b/arch/riscv/kvm/aia_imsic.c
index 2dc09dcb8ab5..8f108cfa80e5 100644
--- a/arch/riscv/kvm/aia_imsic.c
+++ b/arch/riscv/kvm/aia_imsic.c
@@ -277,6 +277,33 @@ static u32 imsic_mrif_topei(struct imsic_mrif *mrif, u32 nr_eix, u32 nr_msis)
return 0;
}

+static int imsic_mrif_isel_check(u32 nr_eix, unsigned long isel)
+{
+ u32 num = 0;
+
+ switch (isel) {
+ case IMSIC_EIDELIVERY:
+ case IMSIC_EITHRESHOLD:
+ break;
+ case IMSIC_EIP0 ... IMSIC_EIP63:
+ num = isel - IMSIC_EIP0;
+ break;
+ case IMSIC_EIE0 ... IMSIC_EIE63:
+ num = isel - IMSIC_EIE0;
+ break;
+ default:
+ return -ENOENT;
+ };
+#ifndef CONFIG_32BIT
+ if (num & 0x1)
+ return -EINVAL;
+#endif
+ if ((num / 2) >= nr_eix)
+ return -EINVAL;
+
+ return 0;
+}
+
static int imsic_mrif_rmw(struct imsic_mrif *mrif, u32 nr_eix,
unsigned long isel, unsigned long *val,
unsigned long new_val, unsigned long wr_mask)
@@ -407,6 +434,86 @@ static void imsic_vsfile_read(int vsfile_hgei, int vsfile_cpu, u32 nr_eix,
imsic_vsfile_local_read, &idata, 1);
}

+struct imsic_vsfile_rw_data {
+ int hgei;
+ int isel;
+ bool write;
+ unsigned long val;
+};
+
+static void imsic_vsfile_local_rw(void *data)
+{
+ struct imsic_vsfile_rw_data *idata = data;
+ unsigned long new_hstatus, old_hstatus, old_vsiselect;
+
+ old_vsiselect = csr_read(CSR_VSISELECT);
+ old_hstatus = csr_read(CSR_HSTATUS);
+ new_hstatus = old_hstatus & ~HSTATUS_VGEIN;
+ new_hstatus |= ((unsigned long)idata->hgei) << HSTATUS_VGEIN_SHIFT;
+ csr_write(CSR_HSTATUS, new_hstatus);
+
+ switch (idata->isel) {
+ case IMSIC_EIDELIVERY:
+ if (idata->write)
+ imsic_vs_csr_write(IMSIC_EIDELIVERY, idata->val);
+ else
+ idata->val = imsic_vs_csr_read(IMSIC_EIDELIVERY);
+ break;
+ case IMSIC_EITHRESHOLD:
+ if (idata->write)
+ imsic_vs_csr_write(IMSIC_EITHRESHOLD, idata->val);
+ else
+ idata->val = imsic_vs_csr_read(IMSIC_EITHRESHOLD);
+ break;
+ case IMSIC_EIP0 ... IMSIC_EIP63:
+ case IMSIC_EIE0 ... IMSIC_EIE63:
+#ifndef CONFIG_32BIT
+ if (idata->isel & 0x1)
+ break;
+#endif
+ if (idata->write)
+ imsic_eix_write(idata->isel, idata->val);
+ else
+ idata->val = imsic_eix_read(idata->isel);
+ break;
+ default:
+ break;
+ }
+
+ csr_write(CSR_HSTATUS, old_hstatus);
+ csr_write(CSR_VSISELECT, old_vsiselect);
+}
+
+static int imsic_vsfile_rw(int vsfile_hgei, int vsfile_cpu, u32 nr_eix,
+ unsigned long isel, bool write,
+ unsigned long *val)
+{
+ int rc;
+ struct imsic_vsfile_rw_data rdata;
+
+ /* We can only access register if we have a IMSIC VS-file */
+ if (vsfile_cpu < 0 || vsfile_hgei <= 0)
+ return -EINVAL;
+
+ /* Check IMSIC register iselect */
+ rc = imsic_mrif_isel_check(nr_eix, isel);
+ if (rc)
+ return rc;
+
+ /* We can only access register on local CPU */
+ rdata.hgei = vsfile_hgei;
+ rdata.isel = isel;
+ rdata.write = write;
+ rdata.val = (write) ? *val : 0;
+ on_each_cpu_mask(cpumask_of(vsfile_cpu),
+ imsic_vsfile_local_rw, &rdata, 1);
+
+ if (!write)
+ *val = rdata.val;
+
+ return 0;
+}
+
static void imsic_vsfile_local_clear(int vsfile_hgei, u32 nr_eix)
{
u32 i;
@@ -758,6 +865,69 @@ int kvm_riscv_vcpu_aia_imsic_rmw(struct kvm_vcpu *vcpu, unsigned long isel,
return rc;
}

+int kvm_riscv_aia_imsic_rw_attr(struct kvm *kvm, unsigned long type,
+ bool write, unsigned long *val)
+{
+ u32 isel, vcpu_id;
+ unsigned long flags;
+ struct imsic *imsic;
+ struct kvm_vcpu *vcpu;
+ int rc, vsfile_hgei, vsfile_cpu;
+
+ if (!kvm_riscv_aia_initialized(kvm))
+ return -ENODEV;
+
+ vcpu_id = KVM_DEV_RISCV_AIA_IMSIC_GET_VCPU(type);
+ vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
+ if (!vcpu)
+ return -ENODEV;
+
+ isel = KVM_DEV_RISCV_AIA_IMSIC_GET_ISEL(type);
+ imsic = vcpu->arch.aia_context.imsic_state;
+
+ read_lock_irqsave(&imsic->vsfile_lock, flags);
+
+ rc = 0;
+ vsfile_hgei = imsic->vsfile_hgei;
+ vsfile_cpu = imsic->vsfile_cpu;
+ if (vsfile_cpu < 0) {
+ if (write) {
+ rc = imsic_mrif_rmw(imsic->swfile, imsic->nr_eix,
+ isel, NULL, *val, -1UL);
+ imsic_swfile_extirq_update(vcpu);
+ } else
+ rc = imsic_mrif_rmw(imsic->swfile, imsic->nr_eix,
+ isel, val, 0, 0);
+ }
+
+ read_unlock_irqrestore(&imsic->vsfile_lock, flags);
+
+ if (!rc && vsfile_cpu >= 0)
+ rc = imsic_vsfile_rw(vsfile_hgei, vsfile_cpu, imsic->nr_eix,
+ isel, write, val);
+
+ return rc;
+}
+
+int kvm_riscv_aia_imsic_has_attr(struct kvm *kvm, unsigned long type)
+{
+ u32 isel, vcpu_id;
+ struct imsic *imsic;
+ struct kvm_vcpu *vcpu;
+
+ if (!kvm_riscv_aia_initialized(kvm))
+ return -ENODEV;
+
+ vcpu_id = KVM_DEV_RISCV_AIA_IMSIC_GET_VCPU(type);
+ vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
+ if (!vcpu)
+ return -ENODEV;
+
+ isel = KVM_DEV_RISCV_AIA_IMSIC_GET_ISEL(type);
+ imsic = vcpu->arch.aia_context.imsic_state;
+ return imsic_mrif_isel_check(imsic->nr_eix, isel);
+}
+
void kvm_riscv_vcpu_aia_imsic_reset(struct kvm_vcpu *vcpu)
{
struct imsic *imsic = vcpu->arch.aia_context.imsic_state;
--
2.34.1

2023-06-15 08:21:35

by Anup Patel

Subject: [PATCH v3 04/10] RISC-V: KVM: Set kvm_riscv_aia_nr_hgei to zero

We hard-code the kvm_riscv_aia_nr_hgei to zero until IMSIC HW
guest file support is added in KVM RISC-V.

Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Atish Patra <[email protected]>
---
arch/riscv/kvm/aia.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kvm/aia.c b/arch/riscv/kvm/aia.c
index c78c06d99e39..3f97575707eb 100644
--- a/arch/riscv/kvm/aia.c
+++ b/arch/riscv/kvm/aia.c
@@ -408,7 +408,7 @@ int kvm_riscv_aia_alloc_hgei(int cpu, struct kvm_vcpu *owner,

raw_spin_unlock_irqrestore(&hgctrl->lock, flags);

- /* TODO: To be updated later by AIA in-kernel irqchip support */
+ /* TODO: To be updated later by AIA IMSIC HW guest file support */
if (hgei_va)
*hgei_va = NULL;
if (hgei_pa)
@@ -610,6 +610,14 @@ int kvm_riscv_aia_init(void)
if (kvm_riscv_aia_nr_hgei)
kvm_riscv_aia_nr_hgei--;

+ /*
+ * Number of usable HGEI lines should be minimum of per-HART
+ * IMSIC guest files and number of bits in HGEIE
+ *
+ * TODO: To be updated later by AIA IMSIC HW guest file support
+ */
+ kvm_riscv_aia_nr_hgei = 0;
+
/* Initialize guest external interrupt line management */
rc = aia_hgei_init();
if (rc)
--
2.34.1

2023-06-15 08:23:11

by Anup Patel

Subject: [PATCH v3 08/10] RISC-V: KVM: Expose APLIC registers as attributes of AIA irqchip

We expose APLIC registers as KVM device attributes of the in-kernel
AIA irqchip device. This will allow KVM user-space to save/restore
APLIC state using KVM device ioctls().

Signed-off-by: Anup Patel <[email protected]>
---
arch/riscv/include/asm/kvm_aia.h | 3 +++
arch/riscv/include/uapi/asm/kvm.h | 6 +++++
arch/riscv/kvm/aia_aplic.c | 43 +++++++++++++++++++++++++++++++
arch/riscv/kvm/aia_device.c | 25 ++++++++++++++++++
4 files changed, 77 insertions(+)

diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
index f6bd8523395f..ba939c0054aa 100644
--- a/arch/riscv/include/asm/kvm_aia.h
+++ b/arch/riscv/include/asm/kvm_aia.h
@@ -129,6 +129,9 @@ static inline void kvm_riscv_vcpu_aia_imsic_cleanup(struct kvm_vcpu *vcpu)
{
}

+int kvm_riscv_aia_aplic_set_attr(struct kvm *kvm, unsigned long type, u32 v);
+int kvm_riscv_aia_aplic_get_attr(struct kvm *kvm, unsigned long type, u32 *v);
+int kvm_riscv_aia_aplic_has_attr(struct kvm *kvm, unsigned long type);
int kvm_riscv_aia_aplic_inject(struct kvm *kvm, u32 source, bool level);
int kvm_riscv_aia_aplic_init(struct kvm *kvm);
void kvm_riscv_aia_aplic_cleanup(struct kvm *kvm);
diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
index 047c8fc5bd71..9ed822fc5589 100644
--- a/arch/riscv/include/uapi/asm/kvm.h
+++ b/arch/riscv/include/uapi/asm/kvm.h
@@ -249,6 +249,12 @@ enum KVM_RISCV_SBI_EXT_ID {
#define KVM_DEV_RISCV_AIA_GRP_CTRL 2
#define KVM_DEV_RISCV_AIA_CTRL_INIT 0

+/*
+ * The device attribute type contains the memory mapped offset of the
+ * APLIC register (range 0x0000-0x3FFF) and it must be 4-byte aligned.
+ */
+#define KVM_DEV_RISCV_AIA_GRP_APLIC 3
+
/* One single KVM irqchip, ie. the AIA */
#define KVM_NR_IRQCHIPS 1

diff --git a/arch/riscv/kvm/aia_aplic.c b/arch/riscv/kvm/aia_aplic.c
index eecd8f4abe21..39e72aa016a4 100644
--- a/arch/riscv/kvm/aia_aplic.c
+++ b/arch/riscv/kvm/aia_aplic.c
@@ -501,6 +501,49 @@ static struct kvm_io_device_ops aplic_iodoev_ops = {
.write = aplic_mmio_write,
};

+int kvm_riscv_aia_aplic_set_attr(struct kvm *kvm, unsigned long type, u32 v)
+{
+ int rc;
+
+ if (!kvm->arch.aia.aplic_state)
+ return -ENODEV;
+
+ rc = aplic_mmio_write_offset(kvm, type, v);
+ if (rc)
+ return rc;
+
+ return 0;
+}
+
+int kvm_riscv_aia_aplic_get_attr(struct kvm *kvm, unsigned long type, u32 *v)
+{
+ int rc;
+
+ if (!kvm->arch.aia.aplic_state)
+ return -ENODEV;
+
+ rc = aplic_mmio_read_offset(kvm, type, v);
+ if (rc)
+ return rc;
+
+ return 0;
+}
+
+int kvm_riscv_aia_aplic_has_attr(struct kvm *kvm, unsigned long type)
+{
+ int rc;
+ u32 val;
+
+ if (!kvm->arch.aia.aplic_state)
+ return -ENODEV;
+
+ rc = aplic_mmio_read_offset(kvm, type, &val);
+ if (rc)
+ return rc;
+
+ return 0;
+}
+
int kvm_riscv_aia_aplic_init(struct kvm *kvm)
{
int i, ret = 0;
diff --git a/arch/riscv/kvm/aia_device.c b/arch/riscv/kvm/aia_device.c
index 7ab555121872..c649ad6e8e0a 100644
--- a/arch/riscv/kvm/aia_device.c
+++ b/arch/riscv/kvm/aia_device.c
@@ -365,6 +365,15 @@ static int aia_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
break;
}

+ break;
+ case KVM_DEV_RISCV_AIA_GRP_APLIC:
+ if (copy_from_user(&nr, uaddr, sizeof(nr)))
+ return -EFAULT;
+
+ mutex_lock(&dev->kvm->lock);
+ r = kvm_riscv_aia_aplic_set_attr(dev->kvm, type, nr);
+ mutex_unlock(&dev->kvm->lock);
+
break;
}

@@ -412,6 +421,20 @@ static int aia_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
if (copy_to_user(uaddr, &addr, sizeof(addr)))
return -EFAULT;

+ break;
+ case KVM_DEV_RISCV_AIA_GRP_APLIC:
+ if (copy_from_user(&nr, uaddr, sizeof(nr)))
+ return -EFAULT;
+
+ mutex_lock(&dev->kvm->lock);
+ r = kvm_riscv_aia_aplic_get_attr(dev->kvm, type, &nr);
+ mutex_unlock(&dev->kvm->lock);
+ if (r)
+ return r;
+
+ if (copy_to_user(uaddr, &nr, sizeof(nr)))
+ return -EFAULT;
+
break;
}

@@ -448,6 +471,8 @@ static int aia_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
return 0;
}
break;
+ case KVM_DEV_RISCV_AIA_GRP_APLIC:
+ return kvm_riscv_aia_aplic_has_attr(dev->kvm, attr->attr);
}

return -ENXIO;
--
2.34.1

2023-06-16 07:53:12

by Atish Patra

Subject: Re: [PATCH v3 08/10] RISC-V: KVM: Expose APLIC registers as attributes of AIA irqchip

On Thu, Jun 15, 2023 at 12:34 AM Anup Patel <[email protected]> wrote:
>
> We expose APLIC registers as KVM device attributes of the in-kernel
> AIA irqchip device. This will allow KVM user-space to save/restore
> APLIC state using KVM device ioctls().
>
> Signed-off-by: Anup Patel <[email protected]>
> ---
> arch/riscv/include/asm/kvm_aia.h | 3 +++
> arch/riscv/include/uapi/asm/kvm.h | 6 +++++
> arch/riscv/kvm/aia_aplic.c | 43 +++++++++++++++++++++++++++++++
> arch/riscv/kvm/aia_device.c | 25 ++++++++++++++++++
> 4 files changed, 77 insertions(+)
>
> diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
> index f6bd8523395f..ba939c0054aa 100644
> --- a/arch/riscv/include/asm/kvm_aia.h
> +++ b/arch/riscv/include/asm/kvm_aia.h
> @@ -129,6 +129,9 @@ static inline void kvm_riscv_vcpu_aia_imsic_cleanup(struct kvm_vcpu *vcpu)
> {
> }
>
> +int kvm_riscv_aia_aplic_set_attr(struct kvm *kvm, unsigned long type, u32 v);
> +int kvm_riscv_aia_aplic_get_attr(struct kvm *kvm, unsigned long type, u32 *v);
> +int kvm_riscv_aia_aplic_has_attr(struct kvm *kvm, unsigned long type);
> int kvm_riscv_aia_aplic_inject(struct kvm *kvm, u32 source, bool level);
> int kvm_riscv_aia_aplic_init(struct kvm *kvm);
> void kvm_riscv_aia_aplic_cleanup(struct kvm *kvm);
> diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
> index 047c8fc5bd71..9ed822fc5589 100644
> --- a/arch/riscv/include/uapi/asm/kvm.h
> +++ b/arch/riscv/include/uapi/asm/kvm.h
> @@ -249,6 +249,12 @@ enum KVM_RISCV_SBI_EXT_ID {
> #define KVM_DEV_RISCV_AIA_GRP_CTRL 2
> #define KVM_DEV_RISCV_AIA_CTRL_INIT 0
>
> +/*
> + * The device attribute type contains the memory mapped offset of the
> + * APLIC register (range 0x0000-0x3FFF) and it must be 4-byte aligned.
> + */
> +#define KVM_DEV_RISCV_AIA_GRP_APLIC 3
> +
> /* One single KVM irqchip, ie. the AIA */
> #define KVM_NR_IRQCHIPS 1
>
> diff --git a/arch/riscv/kvm/aia_aplic.c b/arch/riscv/kvm/aia_aplic.c
> index eecd8f4abe21..39e72aa016a4 100644
> --- a/arch/riscv/kvm/aia_aplic.c
> +++ b/arch/riscv/kvm/aia_aplic.c
> @@ -501,6 +501,49 @@ static struct kvm_io_device_ops aplic_iodoev_ops = {
> .write = aplic_mmio_write,
> };
>
> +int kvm_riscv_aia_aplic_set_attr(struct kvm *kvm, unsigned long type, u32 v)
> +{
> + int rc;
> +
> + if (!kvm->arch.aia.aplic_state)
> + return -ENODEV;
> +
> + rc = aplic_mmio_write_offset(kvm, type, v);
> + if (rc)
> + return rc;
> +
> + return 0;
> +}
> +
> +int kvm_riscv_aia_aplic_get_attr(struct kvm *kvm, unsigned long type, u32 *v)
> +{
> + int rc;
> +
> + if (!kvm->arch.aia.aplic_state)
> + return -ENODEV;
> +
> + rc = aplic_mmio_read_offset(kvm, type, v);
> + if (rc)
> + return rc;
> +
> + return 0;
> +}
> +
> +int kvm_riscv_aia_aplic_has_attr(struct kvm *kvm, unsigned long type)
> +{
> + int rc;
> + u32 val;
> +
> + if (!kvm->arch.aia.aplic_state)
> + return -ENODEV;
> +
> + rc = aplic_mmio_read_offset(kvm, type, &val);
> + if (rc)
> + return rc;
> +
> + return 0;
> +}
> +
> int kvm_riscv_aia_aplic_init(struct kvm *kvm)
> {
> int i, ret = 0;
> diff --git a/arch/riscv/kvm/aia_device.c b/arch/riscv/kvm/aia_device.c
> index 7ab555121872..c649ad6e8e0a 100644
> --- a/arch/riscv/kvm/aia_device.c
> +++ b/arch/riscv/kvm/aia_device.c
> @@ -365,6 +365,15 @@ static int aia_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
> break;
> }
>
> + break;
> + case KVM_DEV_RISCV_AIA_GRP_APLIC:
> + if (copy_from_user(&nr, uaddr, sizeof(nr)))
> + return -EFAULT;
> +
> + mutex_lock(&dev->kvm->lock);
> + r = kvm_riscv_aia_aplic_set_attr(dev->kvm, type, nr);
> + mutex_unlock(&dev->kvm->lock);
> +
> break;
> }
>
> @@ -412,6 +421,20 @@ static int aia_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
> if (copy_to_user(uaddr, &addr, sizeof(addr)))
> return -EFAULT;
>
> + break;
> + case KVM_DEV_RISCV_AIA_GRP_APLIC:
> + if (copy_from_user(&nr, uaddr, sizeof(nr)))
> + return -EFAULT;
> +
> + mutex_lock(&dev->kvm->lock);
> + r = kvm_riscv_aia_aplic_get_attr(dev->kvm, type, &nr);
> + mutex_unlock(&dev->kvm->lock);
> + if (r)
> + return r;
> +
> + if (copy_to_user(uaddr, &nr, sizeof(nr)))
> + return -EFAULT;
> +
> break;
> }
>
> @@ -448,6 +471,8 @@ static int aia_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
> return 0;
> }
> break;
> + case KVM_DEV_RISCV_AIA_GRP_APLIC:
> + return kvm_riscv_aia_aplic_has_attr(dev->kvm, attr->attr);
> }
>
> return -ENXIO;
> --
> 2.34.1
>


Reviewed-by: Atish Patra <[email protected]>
--
Regards,
Atish

2023-06-18 16:46:16

by Anup Patel

Subject: Re: [PATCH v3 00/10] RISC-V KVM in-kernel AIA irqchip

On Thu, Jun 15, 2023 at 1:04 PM Anup Patel <[email protected]> wrote:
>
> This series adds in-kernel AIA irqchip to KVM RISC-V which trap-n-emulate
> IMSIC and APLIC MSI-mode for Guest. The APLIC MSI-mode trap-n-emulate is
> optional so KVM user space can emulate APLIC entirely in user space.
>
> The use of IMSIC HW guest files to accelerate IMSIC virtualization will be
> done as separate series since this depends on AIA irqchip drivers to be
> upstreamed. This series has no dependency on the AIA irqchip drivers.
>
> There is also a KVM AIA irq-bypass (or device MSI virtualization) series
> under development which depends on this series and upcoming IOMMU driver
> series.
>
> These patches (or this series) can also be found in the
> riscv_kvm_aia_irqchip_v3 branch at: https://github.com/avpatel/linux.git
>
> Changes since v2:
> - Added KVM_CAP_IRQCHIP in PATCH5
> - Fix check for KVM_DEV_RISCV_AIA_CONFIG_IDS write in PATCH6
> - Fix APLIC_IRQ_STATE_ENPEND usage in PATCH7
>
> Changes since v1:
> - Rebased on Linux-6.4-rc6
> - Addressed Atish's comment in PATCH6
> - Added comments in arch/riscv/include/uapi/asm/kvm.h about APLIC and
> IMSIC device attribute type
>
> Anup Patel (10):
> RISC-V: KVM: Implement guest external interrupt line management
> RISC-V: KVM: Add IMSIC related defines
> RISC-V: KVM: Add APLIC related defines
> RISC-V: KVM: Set kvm_riscv_aia_nr_hgei to zero
> RISC-V: KVM: Skeletal in-kernel AIA irqchip support
> RISC-V: KVM: Implement device interface for AIA irqchip
> RISC-V: KVM: Add in-kernel emulation of AIA APLIC
> RISC-V: KVM: Expose APLIC registers as attributes of AIA irqchip
> RISC-V: KVM: Add in-kernel virtualization of AIA IMSIC
> RISC-V: KVM: Expose IMSIC registers as attributes of AIA irqchip

Queued this series for 6.5

Regards,
Anup

>
> arch/riscv/include/asm/kvm_aia.h | 107 ++-
> arch/riscv/include/asm/kvm_aia_aplic.h | 58 ++
> arch/riscv/include/asm/kvm_aia_imsic.h | 38 +
> arch/riscv/include/asm/kvm_host.h | 4 +
> arch/riscv/include/uapi/asm/kvm.h | 72 ++
> arch/riscv/kvm/Kconfig | 4 +
> arch/riscv/kvm/Makefile | 3 +
> arch/riscv/kvm/aia.c | 274 +++++-
> arch/riscv/kvm/aia_aplic.c | 619 ++++++++++++++
> arch/riscv/kvm/aia_device.c | 673 +++++++++++++++
> arch/riscv/kvm/aia_imsic.c | 1083 ++++++++++++++++++++++++
> arch/riscv/kvm/main.c | 3 +-
> arch/riscv/kvm/vcpu.c | 2 +
> arch/riscv/kvm/vm.c | 118 +++
> include/uapi/linux/kvm.h | 2 +
> 15 files changed, 3027 insertions(+), 33 deletions(-)
> create mode 100644 arch/riscv/include/asm/kvm_aia_aplic.h
> create mode 100644 arch/riscv/include/asm/kvm_aia_imsic.h
> create mode 100644 arch/riscv/kvm/aia_aplic.c
> create mode 100644 arch/riscv/kvm/aia_device.c
> create mode 100644 arch/riscv/kvm/aia_imsic.c
>
> --
> 2.34.1
>
>
> --
> kvm-riscv mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/kvm-riscv